Daniel Veillard | 09ab7e1 | 2001-07-10 15:49:44 +0000 | [diff] [blame] | 1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" |
| 2 | "http://www.w3.org/TR/html4/loose.dtd"> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 3 | <html> |
| 4 | <head> |
Daniel Veillard | ec78c0f | 2000-08-25 10:25:23 +0000 | [diff] [blame] | 5 | <title>The XML C library for Gnome</title> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 6 | <meta name="GENERATOR" content="amaya V5.0"> |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 7 | <meta http-equiv="Content-Type" content="text/html"> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 8 | </head> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 9 | |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 10 | <body bgcolor="#ffffff"> |
Daniel Veillard | ec78c0f | 2000-08-25 10:25:23 +0000 | [diff] [blame] | 11 | <h1 align="center">The XML C library for Gnome</h1> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 12 | |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 13 | <h1>Note: this is the flat content of the <a href="index.html">web |
| 14 | site</a></h1> |
| 15 | |
Daniel Veillard | c948420 | 2001-10-24 12:35:52 +0000 | [diff] [blame] | 16 | <h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 17 | |
| 18 | <p></p> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 19 | |
| 20 | <p>Libxml is the XML C library developped for the Gnome project. XML itself |
| 21 | is a metalanguage to design markup languages, i.e. text language where |
| 22 | semantic and structure are added to the content using extra "markup" |
| 23 | information enclosed between angle bracket. HTML is the most well-known |
| 24 | markup language.</p> |
| 25 | |
| 26 | <p>Libxml2 implements a number of existing standards related to markup |
| 27 | languages:</p> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 28 | <ul> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 29 | <li>the XML standard: <a |
| 30 | href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li> |
| 31 | <li>Namespaces in XML: <a |
| 32 | href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li> |
| 33 | <li>XML Base: <a |
| 34 | href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li> |
| 35 | <li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 36 | : Uniform Resource Identifiers <a |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 37 | href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li> |
| 38 | <li>XML Path Language (XPath) 1.0: <a |
| 39 | href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li> |
| 40 | <li>HTML4 parser: <a |
| 41 | href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li> |
| 42 | <li>most of XML Pointer Language (XPointer) Version 1.0: <a |
| 43 | href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li> |
| 44 | <li>XML Inclusions (XInclude) Version 1.0: <a |
| 45 | href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li> |
| 46 | <li>[ISO-8859-1], <a |
| 47 | href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8] |
| 48 | and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a> |
| 49 | [UTF-16] core encodings</li> |
| 50 | <li>part of SGML Open Technical Resolution TR9401:1997</li> |
| 51 | <li>XML Catalogs Working Draft 06 August 2001: <a |
| 52 | href="http://www.oasis-open.org/committees/entity/spec-2001-08-06.html">http://www.oasis-open.org/committees/entity/spec-2001-08-06.html</a></li> |
Daniel Veillard | 9698445 | 2000-08-31 13:50:12 +0000 | [diff] [blame] | 53 | </ul> |
| 54 | |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 55 | <p>In most cases libxml tries to implement the specifications in a relatively |
| 56 | strict way. To some extent libxml2 provide some support for the following |
| 57 | other specification but don't claim to implement them:</p> |
| 58 | <ul> |
| 59 | <li>Document Object Model (DOM) <a |
| 60 | href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a> |
| 61 | it doesn't implement the API itself, gdome2 does this in top of |
| 62 | libxml2</li> |
| 63 | <li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 64 | : libxml implements a basic FTP client code</li> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 65 | <li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 66 | : HTTP/1.0, again a basic HTTP client code</li> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 67 | <li>SAX: a minimal SAX implementation compatible with early expat |
| 68 | versions</li> |
| 69 | <li>DocBook SGML v4: libxml2 includes a hackish parser to transition to |
| 70 | XML</li> |
| 71 | </ul> |
| 72 | |
Daniel Veillard | 845cce4 | 2002-01-09 11:51:37 +0000 | [diff] [blame] | 73 | <p>Libxml2 is known to be very portable, should build and work without |
| 74 | serious troubles on a variety of systems (Linux, Unix, Windows, CygWin, |
| 75 | MacOs, MacOsX, RISC Os, OS/2, VMS, QNX, MVS, ...)</p> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 76 | |
Daniel Veillard | 9698445 | 2000-08-31 13:50:12 +0000 | [diff] [blame] | 77 | <p>Separate documents:</p> |
| 78 | <ul> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 79 | <li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> |
| 80 | providing an implementation of XSLT 1.0 and extensions on top of |
| 81 | libxml2</li> |
| 82 | <li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a> |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 83 | : a standard DOM2 implementation based on libxml2</li> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 84 | </ul> |
| 85 | |
| 86 | <h2><a name="Introducti">Introduction</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 87 | |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 88 | <p>This document describes libxml, the <a |
Daniel Veillard | ec78c0f | 2000-08-25 10:25:23 +0000 | [diff] [blame] | 89 | href="http://www.w3.org/XML/">XML</a> C library developped for the <a |
| 90 | href="http://www.gnome.org/">Gnome</a> project. <a |
| 91 | href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based |
| 92 | structured documents/data.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 93 | |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 94 | <p>Here are some key points about libxml:</p> |
| 95 | <ul> |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 96 | <li>Libxml exports Push and Pull type parser interfaces for both XML and |
| 97 | HTML.</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 98 | <li>Libxml can do DTD validation at parse time, using a parsed document |
| 99 | instance, or with an arbitrary DTD.</li> |
| 100 | <li>Libxml now includes nearly complete <a |
Daniel Veillard | 8c2ecaf | 2001-07-10 17:53:07 +0000 | [diff] [blame] | 101 | href="http://www.w3.org/TR/xpath">XPath</a>, <a |
| 102 | href="http://www.w3.org/TR/xptr">XPointer</a> and <a |
| 103 | href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li> |
Daniel Veillard | ec78c0f | 2000-08-25 10:25:23 +0000 | [diff] [blame] | 104 | <li>It is written in plain C, making as few assumptions as possible, and |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 105 | sticking closely to ANSI C/POSIX for easy embedding. Works on |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 106 | Linux/Unix/Windows, ported to a number of other platforms.</li> |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 107 | <li>Basic support for HTTP and FTP client allowing aplications to fetch |
| 108 | remote resources</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 109 | <li>The design is modular, most of the extensions can be compiled out.</li> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 110 | <li>The internal document repesentation is as close as possible to the <a |
| 111 | href="http://www.w3.org/DOM/">DOM</a> interfaces.</li> |
| 112 | <li>Libxml also has a <a href="http://www.megginson.com/SAX/index.html">SAX |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 113 | like interface</a>; the interface is designed to be compatible with <a |
| 114 | href="http://www.jclark.com/xml/expat.html">Expat</a>.</li> |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 115 | <li>This library is released both under the <a |
| 116 | href="http://www.w3.org/Consortium/Legal/copyright-software-19980720.html">W3C |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 117 | IPR</a> and the <a href="http://www.gnu.org/copyleft/lesser.html">GNU |
| 118 | LGPL</a>. Use either at your convenience, basically this should make |
| 119 | everybody happy, if not, drop me a mail.</li> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 120 | </ul> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 121 | |
Daniel Veillard | e0c1d72 | 2001-03-21 10:28:36 +0000 | [diff] [blame] | 122 | <p>Warning: unless you are forced to because your application links with a |
| 123 | Gnome library requiring it, <strong><span |
| 124 | style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use |
| 125 | libxml2</p> |
| 126 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 127 | <h2><a name="FAQ">FAQ</a></h2> |
| 128 | |
| 129 | <p>Table of Content:</p> |
| 130 | <ul> |
| 131 | <li><a href="FAQ.html#Licence">Licence(s)</a></li> |
| 132 | <li><a href="FAQ.html#Installati">Installation</a></li> |
| 133 | <li><a href="FAQ.html#Compilatio">Compilation</a></li> |
| 134 | <li><a href="FAQ.html#Developer">Developer corner</a></li> |
| 135 | </ul> |
| 136 | |
| 137 | <h3><a name="Licence">Licence</a>(s)</h3> |
| 138 | <ol> |
| 139 | <li><em>Licensing Terms for libxml</em> |
| 140 | <p>libxml is released under 2 (compatible) licences:</p> |
| 141 | <ul> |
| 142 | <li>the <a href="http://www.gnu.org/copyleft/lgpl.html">LGPL</a>: GNU |
| 143 | Library General Public License</li> |
| 144 | <li>the <a |
| 145 | href="http://www.w3.org/Consortium/Legal/copyright-software-19980720.html">W3C |
| 146 | IPR</a>: very similar to the XWindow licence</li> |
| 147 | </ul> |
| 148 | </li> |
| 149 | <li><em>Can I embed libxml in a proprietary application ?</em> |
| 150 | <p>Yes. The W3C IPR allows you to also keep proprietary the changes you |
| 151 | made to libxml, but it would be graceful to provide back bugfixes and |
| 152 | improvements as patches for possible incorporation in the main |
| 153 | development tree</p> |
| 154 | </li> |
| 155 | </ol> |
| 156 | |
| 157 | <h3><a name="Installati">Installation</a></h3> |
| 158 | <ol> |
| 159 | <li>Unless you are forced to because your application links with a Gnome |
| 160 | library requiring it, <strong><span style="background-color: #FF0000">Do |
| 161 | Not Use libxml1</span></strong>, use libxml2</li> |
| 162 | <li><em>Where can I get libxml</em> |
| 163 | ? |
| 164 | <p>The original distribution comes from <a |
| 165 | href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a |
| 166 | href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">gnome.org</a></p> |
| 167 | <p>Most linux and Bsd distribution includes libxml, this is probably the |
| 168 | safer way for end-users</p> |
| 169 | <p>David Doolin provides precompiled Windows versions at <a |
| 170 | href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p> |
| 171 | </li> |
| 172 | <li><em>I see libxml and libxml2 releases, which one should I install ?</em> |
| 173 | <ul> |
| 174 | <li>If you are not concerned by any existing backward compatibility |
| 175 | with existing application, install libxml2 only</li> |
| 176 | <li>If you are not doing development, you can safely install both. |
| 177 | usually the packages <a |
| 178 | href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a |
| 179 | href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are |
| 180 | compatible (this is not the case for development packages)</li> |
| 181 | <li>If you are a developer and your system provides separate packaging |
| 182 | for shared libraries and the development components, it is possible |
| 183 | to install libxml and libxml2, and also <a |
| 184 | href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a> |
| 185 | and <a |
| 186 | href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a> |
| 187 | too for libxml2 >= 2.3.0</li> |
| 188 | <li>If you are developing a new application, please develop against |
| 189 | libxml2(-devel)</li> |
| 190 | </ul> |
| 191 | </li> |
| 192 | <li><em>I can't install the libxml package it conflicts with libxml0</em> |
| 193 | <p>You probably have an old libxml0 package used to provide the shared |
| 194 | library for libxml.so.0, you can probably safely remove it. Anyway the |
| 195 | libxml packages provided on <a |
| 196 | href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provides |
| 197 | libxml.so.0</p> |
| 198 | </li> |
| 199 | <li><em>I can't install the libxml(2) RPM package due to failed |
| 200 | dependancies</em> |
| 201 | <p>The most generic solution is to refetch the latest src.rpm , and |
| 202 | rebuild it locally with</p> |
| 203 | <p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code></p> |
| 204 | <p>if everything goes well it will generate two binary rpm (one providing |
| 205 | the shared libs and xmllint, and the other one, the -devel package |
| 206 | providing includes, static libraries and scripts needed to build |
| 207 | applications with libxml(2)) that you can install locally.</p> |
| 208 | </li> |
| 209 | </ol> |
| 210 | |
| 211 | <h3><a name="Compilatio">Compilation</a></h3> |
| 212 | <ol> |
| 213 | <li><em>What is the process to compile libxml ?</em> |
| 214 | <p>As most UNIX libraries libxml follows the "standard":</p> |
| 215 | <p><code>gunzip -c xxx.tar.gz | tar xvf -</code></p> |
| 216 | <p><code>cd libxml-xxxx</code></p> |
| 217 | <p><code>./configure --help</code></p> |
| 218 | <p>to see the options, then the compilation/installation proper</p> |
| 219 | <p><code>./configure [possible options]</code></p> |
| 220 | <p><code>make</code></p> |
| 221 | <p><code>make install</code></p> |
| 222 | <p>At that point you may have to rerun ldconfig or similar utility to |
| 223 | update your list of installed shared libs.</p> |
| 224 | </li> |
| 225 | <li><em>What other libraries are needed to compile/install libxml ?</em> |
| 226 | <p>Libxml does not requires any other library, the normal C ANSI API |
| 227 | should be sufficient (please report any violation to this rule you may |
| 228 | find).</p> |
| 229 | <p>However if found at configuration time libxml will detect and use the |
| 230 | following libs:</p> |
| 231 | <ul> |
| 232 | <li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> |
| 233 | : a highly portable and available widely compression library</li> |
| 234 | <li>iconv: a powerful character encoding conversion library. It's |
| 235 | included by default on recent glibc libraries, so it doesn't need to |
| 236 | be installed specifically on linux. It seems it's now <a |
| 237 | href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part |
| 238 | of the official UNIX</a> specification. Here is one <a |
| 239 | href="http://clisp.cons.org/~haible/packages-libiconv.html">implementation |
| 240 | of the library</a> which source can be found <a |
| 241 | href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li> |
| 242 | </ul> |
| 243 | </li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 244 | <li><em>make check fails on some platforms</em> |
| 245 | <p>Sometime the regression tests results don't completely match the value |
| 246 | produced by the parser, and the makefile uses diff to print the delta. On |
| 247 | some platforms the diff return breaks the compilation process, if the |
| 248 | diff is small this is probably not a serious problem</p> |
| 249 | </li> |
| 250 | <li><em>I use the CVS version and there is no configure script</em> |
| 251 | <p>The configure (and other Makefiles) are generated. Use the autogen.sh |
| 252 | script to regenerate the configure and Makefiles, like:</p> |
| 253 | <p><code>./autogen.sh --prefix=/usr --disable-shared</code></p> |
| 254 | </li> |
| 255 | <li><em>I have troubles when running make tests with gcc-3.0</em> |
| 256 | <p>It seems the initial release of gcc-3.0 has a problem with the |
| 257 | optimizer which miscompiles the URI module. Please use another |
| 258 | compiler</p> |
| 259 | </li> |
| 260 | </ol> |
| 261 | |
| 262 | <h3><a name="Developer">Developer</a> corner</h3> |
| 263 | <ol> |
| 264 | <li><em>xmlDocDump() generates output on one line</em> |
| 265 | <p>libxml will not <strong>invent</strong> spaces in the content of a |
| 266 | document since <strong>all spaces in the content of a document are |
| 267 | significant</strong>. If you build a tree from the API and want |
| 268 | indentation:</p> |
| 269 | <ol> |
| 270 | <li>the correct way is to generate those yourself too</li> |
| 271 | <li>the dangerous way is to ask libxml to add those blanks to your |
| 272 | content <strong>modifying the content of your document in the |
| 273 | process</strong>. The result may not be what you expect. There is |
| 274 | <strong>NO</strong> way to guarantee that such a modification won't |
| 275 | impact other part of the content of your document. See <a |
| 276 | href="http://xmlsoft.org/html/libxml-parser.html#XMLKEEPBLANKSDEFAULT">xmlKeepBlanksDefault |
| 277 | ()</a> and <a |
| 278 | href="http://xmlsoft.org/html/libxml-tree.html#XMLSAVEFORMATFILE">xmlSaveFormatFile |
| 279 | ()</a></li> |
| 280 | </ol> |
| 281 | </li> |
| 282 | <li>Extra nodes in the document: |
| 283 | <p><em>For a XML file as below:</em></p> |
| 284 | <pre><?xml version="1.0"?> |
| 285 | <PLAN xmlns="http://www.argus.ca/autotest/1.0/"> |
| 286 | <NODE CommFlag="0"/> |
| 287 | <NODE CommFlag="1"/> |
| 288 | </PLAN></pre> |
| 289 | <p><em>after parsing it with the function |
| 290 | pxmlDoc=xmlParseFile(...);</em></p> |
| 291 | <p><em>I want to the get the content of the first node (node with the |
| 292 | CommFlag="0")</em></p> |
| 293 | <p><em>so I did it as following;</em></p> |
| 294 | <pre>xmlNodePtr pode; |
| 295 | pnode=pxmlDoc->children->children;</pre> |
| 296 | <p><em>but it does not work. If I change it to</em></p> |
| 297 | <pre>pnode=pxmlDoc->children->children->next;</pre> |
| 298 | <p><em>then it works. Can someone explain it to me.</em></p> |
| 299 | <p></p> |
| 300 | <p>In XML all characters in the content of the document are significant |
| 301 | <strong>including blanks and formatting line breaks</strong>.</p> |
| 302 | <p>The extra nodes you are wondering about are just that, text nodes with |
| 303 | the formatting spaces wich are part of the document but that people tend |
| 304 | to forget. There is a function <a |
| 305 | href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault |
| 306 | ()</a> to remove those at parse time, but that's an heuristic, and its |
| 307 | use should be limited to case where you are sure there is no |
| 308 | mixed-content in the document.</p> |
| 309 | </li> |
| 310 | <li><em>I get compilation errors of existing code like when accessing |
| 311 | <strong>root</strong> or <strong>childs fields</strong> of nodes</em> |
| 312 | <p>You are compiling code developed for libxml version 1 and using a |
| 313 | libxml2 development environment. Either switch back to libxml v1 devel or |
| 314 | even better fix the code to compile with libxml2 (or both) by <a |
| 315 | href="upgrade.html">following the instructions</a>.</p> |
| 316 | </li> |
| 317 | <li><em>I get compilation errors about non existing |
| 318 | <strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong> |
| 319 | fields</em> |
| 320 | <p>The source code you are using has been <a |
| 321 | href="upgrade.html">upgraded</a> to be able to compile with both libxml |
| 322 | and libxml2, but you need to install a more recent version: |
| 323 | libxml(-devel) >= 1.8.8 or libxml2(-devel) >= 2.1.0</p> |
| 324 | </li> |
| 325 | <li><em>XPath implementation looks seriously broken</em> |
| 326 | <p>XPath implementation prior to 2.3.0 was really incomplete, upgrade to |
| 327 | a recent version, the implementation and debug of libxslt generated fixes |
| 328 | for most obvious problems.</p> |
| 329 | </li> |
| 330 | <li><em>The example provided in the web page does not compile</em> |
| 331 | <p>It's hard to maintain the documentation in sync with the code |
| 332 | <grin/> ...</p> |
| 333 | <p>Check the previous points 1/ and 2/ raised before, and send |
| 334 | patches.</p> |
| 335 | </li> |
| 336 | <li><em>Where can I get more examples and informations than in the web |
| 337 | page</em> |
| 338 | <p>Ideally a libxml book would be nice. I have no such plan ... But you |
| 339 | can:</p> |
| 340 | <ul> |
| 341 | <li>check more deeply the <a href="html/libxml-lib.html">existing |
| 342 | generated doc</a></li> |
| 343 | <li>looks for examples of use for libxml function using the Gnome code |
| 344 | for example the following will query the full Gnome CVs base for the |
| 345 | use of the <strong>xmlAddChild()</strong> function: |
| 346 | <p><a |
| 347 | href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p> |
| 348 | <p>This may be slow, a large hardware donation to the gnome project |
| 349 | could cure this :-)</p> |
| 350 | </li> |
| 351 | <li><a |
| 352 | href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Browse |
| 353 | the libxml source</a> |
| 354 | , I try to write code as clean and documented as possible, so |
| 355 | looking at it may be helpful</li> |
| 356 | </ul> |
| 357 | </li> |
| 358 | <li>What about C++ ? |
| 359 | <p>libxml is written in pure C in order to allow easy reuse on a number |
| 360 | of platforms, including embedded systems. I don't intend to convert to |
| 361 | C++.</p> |
| 362 | <p>There is however a C++ wrapper provided by Ari Johnson |
| 363 | <ari@btigate.com> which may fullfill your needs:</p> |
| 364 | <p>Website: <a |
| 365 | href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p> |
| 366 | <p>Download: <a |
| 367 | href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p> |
| 368 | </li> |
| 369 | <li>How to validate a document a posteriori ? |
| 370 | <p>It is possible to validate documents which had not been validated at |
| 371 | initial parsing time or documents who have been built from scratch using |
| 372 | the API. Use the <a |
| 373 | href="http://xmlsoft.org/html/libxml-valid.html#XMLVALIDATEDTD">xmlValidateDtd()</a> |
| 374 | function. It is also possible to simply add a Dtd to an existing |
| 375 | document:</p> |
| 376 | <pre>xmlDocPtr doc; /* your existing document */ |
| 377 | xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */ |
| 378 | dtd->name = xmlStrDup((xmlChar*)"root_name"); /* use the given root */ |
| 379 | |
| 380 | doc->intSubset = dtd; |
| 381 | if (doc->children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd); |
| 382 | else xmlAddPrevSibling(doc->children, (xmlNodePtr)dtd); |
| 383 | </pre> |
| 384 | </li> |
| 385 | <li>etc ...</li> |
| 386 | </ol> |
| 387 | |
| 388 | <p></p> |
| 389 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 390 | <h2><a name="Documentat">Documentation</a></h2> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 391 | |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 392 | <p>There are some on-line resources about using libxml:</p> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 393 | <ol> |
Daniel Veillard | 365e13b | 2000-07-02 07:56:37 +0000 | [diff] [blame] | 394 | <li>Check the <a href="FAQ.html">FAQ</a></li> |
Daniel Veillard | c19fccc | 2000-07-03 11:52:01 +0000 | [diff] [blame] | 395 | <li>Check the <a href="http://xmlsoft.org/html/libxml-lib.html">extensive |
Daniel Veillard | 8c6d6af | 2000-08-25 17:14:13 +0000 | [diff] [blame] | 396 | documentation</a> automatically extracted from code comments (using <a |
| 397 | href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gtk-doc">gtk |
| 398 | doc</a>).</li> |
Daniel Veillard | 8d86964 | 2000-07-14 12:12:59 +0000 | [diff] [blame] | 399 | <li>Look at the documentation about <a href="encoding.html">libxml |
| 400 | internationalization support</a></li> |
Daniel Veillard | bc66f85 | 2002-01-14 09:49:20 +0000 | [diff] [blame] | 401 | <li>This page provides a global overview and <a href="example.html">some |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 402 | examples</a> on how to use libxml.</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 403 | <li><a href="mailto:james@daa.com.au">James Henstridge</a> |
| 404 | wrote <a |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 405 | href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice |
| 406 | documentation</a> explaining how to use the libxml SAX interface.</li> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 407 | <li>George Lebl wrote <a |
| 408 | href="http://www-4.ibm.com/software/developer/library/gnome3/">an article |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 409 | for IBM developerWorks</a> about using libxml.</li> |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 410 | <li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO |
| 411 | file</a></li> |
| 412 | <li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>. If you are |
| 413 | starting a new project using libxml you should really use the 2.x |
| 414 | version.</li> |
Daniel Veillard | 845cce4 | 2002-01-09 11:51:37 +0000 | [diff] [blame] | 415 | <li>And don't forget to look at the <a |
| 416 | href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 417 | </ol> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 418 | |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 419 | <h2><a name="Reporting">Reporting bugs and getting help</a></h2> |
Daniel Veillard | 4c3a203 | 1999-11-19 17:46:26 +0000 | [diff] [blame] | 420 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 421 | <p>Well, bugs or missing features are always possible, and I will make a |
| 422 | point of fixing them in a timely fashion. The best way to report a bug is to |
| 423 | use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome |
| 424 | bug tracking database</a> (make sure to use the "libxml" module name). I look |
| 425 | at reports there regularly and it's good to have a reminder when a bug is |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 426 | still open. Be sure to specify that the bug is for the package libxml.</p> |
Daniel Veillard | 4c3a203 | 1999-11-19 17:46:26 +0000 | [diff] [blame] | 427 | |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 428 | <p>There is also a mailing-list <a |
Daniel Veillard | 3197f16 | 2001-04-04 00:40:08 +0000 | [diff] [blame] | 429 | href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a |
| 430 | href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 431 | href="http://xmlsoft.org/messages">old</a>). To subscribe to this list, |
| 432 | please visit the <a |
| 433 | href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and |
| 434 | follow the instructions. <strong>Do not send code, I won't debug it</strong> |
| 435 | (but patches are really appreciated!).</p> |
Daniel Veillard | 234547b | 2001-07-05 09:46:10 +0000 | [diff] [blame] | 436 | |
Daniel Veillard | 008186f | 2001-09-13 14:24:44 +0000 | [diff] [blame] | 437 | <p>Check the following <strong><span style="color: #FF0000">before |
| 438 | posting</span></strong>:</p> |
Daniel Veillard | 234547b | 2001-07-05 09:46:10 +0000 | [diff] [blame] | 439 | <ul> |
Daniel Veillard | dadd087 | 2001-09-15 09:21:44 +0000 | [diff] [blame] | 440 | <li>read the <a href="FAQ.html">FAQ</a></li> |
Daniel Veillard | 234547b | 2001-07-05 09:46:10 +0000 | [diff] [blame] | 441 | <li>make sure you are <a href="ftp://xmlsoft.org/">using a recent |
| 442 | version</a>, and that the problem still shows up in those</li> |
| 443 | <li>check the <a href="http://mail.gnome.org/archives/xml/">list |
| 444 | archives</a> to see if the problem was reported already, in this case |
Daniel Veillard | e7ead2d | 2001-08-22 23:44:09 +0000 | [diff] [blame] | 445 | there is probably a fix available, similary check the <a |
| 446 | href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 447 | open bugs</a></li> |
Daniel Veillard | 234547b | 2001-07-05 09:46:10 +0000 | [diff] [blame] | 448 | <li>make sure you can reproduce the bug with xmllint or one of the test |
| 449 | programs found in source in the distribution</li> |
| 450 | <li>Please send the command showing the error as well as the input (as an |
| 451 | attachement)</li> |
| 452 | </ul> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 453 | |
Daniel Veillard | dadd087 | 2001-09-15 09:21:44 +0000 | [diff] [blame] | 454 | <p>Then send the bug with associated informations to reproduce it to the <a |
Daniel Veillard | 33a6780 | 2001-03-07 09:44:02 +0000 | [diff] [blame] | 455 | href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml |
Daniel Veillard | 008186f | 2001-09-13 14:24:44 +0000 | [diff] [blame] | 456 | related I will approve it.. Please do not send me mail directly, it makes |
| 457 | things really harder to track and in some cases I'm not the best person to |
| 458 | answer a given question, ask the list instead.</p> |
Daniel Veillard | 4c3a203 | 1999-11-19 17:46:26 +0000 | [diff] [blame] | 459 | |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 460 | <p>Of course, bugs reported with a suggested patch for fixing them will |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 461 | probably be processed faster.</p> |
| 462 | |
| 463 | <p>If you're looking for help, a quick look at <a |
Daniel Veillard | f7ed336 | 2001-08-17 12:01:21 +0000 | [diff] [blame] | 464 | href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 465 | provide the answer, I usually send source samples when answering libxml usage |
Daniel Veillard | 6f0adb5 | 2000-07-03 11:41:26 +0000 | [diff] [blame] | 466 | questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 467 | documentantion</a> is not as polished as I would like (i need to learn more |
| 468 | about Docbook), but it's a good starting point.</p> |
| 469 | |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 470 | <h2><a name="help">How to help</a></h2> |
| 471 | |
| 472 | <p>You can help the project in various ways, the best thing to do first is to |
| 473 | subscribe to the mailing-list as explained before, check the <a |
Daniel Veillard | f7ed336 | 2001-08-17 12:01:21 +0000 | [diff] [blame] | 474 | href="http://mail.gnome.org/archives/xml/">archives </a>and the <a |
| 475 | href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 476 | database:</a>:</p> |
| 477 | <ol> |
| 478 | <li>provide patches when you find problems</li> |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 479 | <li>provide the diffs when you port libxml to a new platform. They may not |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 480 | be integrated in all cases but help pinpointing portability problems |
| 481 | and</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 482 | <li>provide documentation fixes (either as patches to the code comments or |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 483 | as HTML diffs).</li> |
| 484 | <li>provide new documentations pieces (translations, examples, etc ...)</li> |
| 485 | <li>Check the TODO file and try to close one of the items</li> |
| 486 | <li>take one of the points raised in the archive or the bug database and |
Daniel Veillard | e7ead2d | 2001-08-22 23:44:09 +0000 | [diff] [blame] | 487 | provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me |
| 488 | </a>before to avoid synchronization problems and check that the suggested |
| 489 | fix will fit in nicely :-)</li> |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 490 | </ol> |
| 491 | |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 492 | <h2><a name="Downloads">Downloads</a></h2> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 493 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 494 | <p>The latest versions of libxml can be found on <a |
Daniel Veillard | 20c8cf2 | 2001-06-26 22:47:36 +0000 | [diff] [blame] | 495 | href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a |
| 496 | href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a |
| 497 | href="ftp://fr.rpmfind.net/pub/libxml/">France</a>) or on the <a |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 498 | href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 499 | as a <a href="ftp://ftp.gnome.org/pub/GNOME/stable/sources/libxml/">source |
Daniel Veillard | 306be99 | 2000-07-03 12:38:45 +0000 | [diff] [blame] | 500 | archive</a> or <a |
Daniel Veillard | a41123c | 2001-04-22 19:31:20 +0000 | [diff] [blame] | 501 | href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM |
| 502 | packages</a>. (NOTE that you need both the <a |
Daniel Veillard | c19fccc | 2000-07-03 11:52:01 +0000 | [diff] [blame] | 503 | href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a |
| 504 | href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a> |
Daniel Veillard | 9518953 | 2001-07-26 18:30:26 +0000 | [diff] [blame] | 505 | packages installed to compile applications using libxml.) <a |
| 506 | href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> is now the maintainer |
| 507 | of the Windows port, <a |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 508 | href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 509 | provides binaries</a>. <a href="mailto:Gary.Pennington@sun.com">Gary |
Daniel Veillard | 1aadc44 | 2001-11-28 13:10:32 +0000 | [diff] [blame] | 510 | Pennington</a> provides <a href="http://garypennington.net/libxml2/">Solaris |
| 511 | binaries</a>.</p> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 512 | |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 513 | <p><a name="Snapshot">Snapshot:</a></p> |
| 514 | <ul> |
| 515 | <li>Code from the W3C cvs base libxml <a |
Daniel Veillard | 33a6780 | 2001-03-07 09:44:02 +0000 | [diff] [blame] | 516 | href="ftp://xmlsoft.org/cvs-snapshot.tar.gz">cvs-snapshot.tar.gz</a></li> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 517 | <li>Docs, content of the web site, the list archive included <a |
Daniel Veillard | 33a6780 | 2001-03-07 09:44:02 +0000 | [diff] [blame] | 518 | href="ftp://xmlsoft.org/libxml-docs.tar.gz">libxml-docs.tar.gz</a></li> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 519 | </ul> |
| 520 | |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 521 | <p><a name="Contribs">Contributions:</a></p> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 522 | |
| 523 | <p>I do accept external contributions, especially if compiling on another |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 524 | platform, get in touch with me to upload the package, wrappers for various |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 525 | languages have been provided, and can be found in the <a |
| 526 | href="contribs.html">contrib section</a></p> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 527 | |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 528 | <p>Libxml is also available from CVS:</p> |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 529 | <ul> |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 530 | <li><p>The <a |
| 531 | href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Gnome |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 532 | CVS base</a>. Check the <a |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 533 | href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a> |
| 534 | page; the CVS module is <b>gnome-xml</b>.</p> |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 535 | </li> |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 536 | <li>The <strong>libxslt</strong> module is also present there</li> |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 537 | </ul> |
| 538 | |
| 539 | <h2><a name="News">News</a></h2> |
| 540 | |
Daniel Veillard | 944b5ff | 1999-12-15 19:08:24 +0000 | [diff] [blame] | 541 | <h3>CVS only : check the <a |
| 542 | href="http://cvs.gnome.org/lxr/source/gnome-xml/ChangeLog">Changelog</a> file |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 543 | for a really accurate description</h3> |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 544 | |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 545 | <p>Items floating around but not actively worked on, get in touch with me if |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 546 | you want to test those</p> |
| 547 | <ul> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 548 | <li>Implementing <a href="http://xmlsoft.org/XSLT">XSLT</a>, this is done |
| 549 | as a separate C library on top of libxml called libxslt</li> |
Daniel Veillard | 28929b2 | 2000-11-13 18:22:49 +0000 | [diff] [blame] | 550 | <li>Finishing up <a href="http://www.w3.org/TR/xptr">XPointer</a> and <a |
| 551 | href="http://www.w3.org/TR/xinclude">XInclude</a></li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 552 | <li>(seeems working but delayed from release) parsing/import of Docbook |
| 553 | SGML docs</li> |
| 554 | </ul> |
| 555 | |
Daniel Veillard | 744683d | 2002-01-14 17:30:20 +0000 | [diff] [blame^] | 556 | <h3>2.4.13: Jan 14 2001</h3> |
| 557 | <ul> |
| 558 | <li>update of the documentation: John Fleck and Charlie Bozeman</li> |
| 559 | <li>cleanup of timing code from Justin Fletcher</li> |
| 560 | <li>fixes for Windows and initial thread support on Win32: Igor and Serguei |
| 561 | Narojnyi</li> |
| 562 | <li>Cygwin patch from Robert Collins</li> |
| 563 | <li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li> |
| 564 | </ul> |
| 565 | |
Daniel Veillard | ef90ba7 | 2001-12-07 14:24:22 +0000 | [diff] [blame] | 566 | <h3>2.4.12: Dec 7 2001</h3> |
| 567 | <ul> |
| 568 | <li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman), |
| 569 | XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups |
| 570 | (robert)</li> |
| 571 | <li>Eric Lavigne contributed project files for MacOS</li> |
| 572 | <li>some makefiles cleanups</li> |
| 573 | </ul> |
| 574 | |
Daniel Veillard | a487105 | 2001-11-26 13:19:48 +0000 | [diff] [blame] | 575 | <h3>2.4.11: Nov 26 2001</h3> |
| 576 | <ul> |
| 577 | <li>fixed a couple of errors in the includes, fixed a few bugs, some code |
| 578 | cleanups</li> |
| 579 | <li>xmllint man pages improvement by Heiko Rupp</li> |
| 580 | <li>updated VMS build instructions from John A Fotheringham</li> |
| 581 | <li>Windows Makefiles updates from Igor</li> |
| 582 | </ul> |
| 583 | |
Daniel Veillard | 43d3f61 | 2001-11-10 11:57:23 +0000 | [diff] [blame] | 584 | <h3>2.4.10: Nov 10 2001</h3> |
| 585 | <ul> |
| 586 | <li>URI escaping fix (Joel Young)</li> |
| 587 | <li>added xmlGetNodePath() (for paths or XPointers generation)</li> |
| 588 | <li>Fixes namespace handling problems when using DTD and validation</li> |
| 589 | <li>improvements on xmllint: Morus Walter patches for --format and |
| 590 | --encode, Stefan Kost and Heiko Rupp improvements on the --shell</li> |
| 591 | <li>fixes for xmlcatalog linking pointed by Weiqi Gao</li> |
| 592 | <li>fixes to the HTML parser</li> |
| 593 | </ul> |
| 594 | |
| 595 | <h3>2.4.9: Nov 6 2001</h3> |
| 596 | <ul> |
| 597 | <li>fixes more catalog bugs</li> |
| 598 | <li>avoid a compilation problem, improve xmlGetLineNo()</li> |
| 599 | </ul> |
| 600 | |
Daniel Veillard | ed421aa | 2001-11-04 21:22:45 +0000 | [diff] [blame] | 601 | <h3>2.4.8: Nov 4 2001</h3> |
| 602 | <ul> |
| 603 | <li>fixed SGML catalogs broken in previous release, updated xmlcatalog |
| 604 | tool</li> |
| 605 | <li>fixed a compile errors and some includes troubles.</li> |
| 606 | </ul> |
| 607 | |
Daniel Veillard | 52dcab3 | 2001-10-30 12:51:17 +0000 | [diff] [blame] | 608 | <h3>2.4.7: Oct 30 2001</h3> |
| 609 | <ul> |
| 610 | <li>exported some debugging interfaces</li> |
| 611 | <li>serious rewrite of the catalog code</li> |
| 612 | <li>integrated Gary Pennington thread safety patch, added configure option |
| 613 | and regression tests</li> |
| 614 | <li>removed an HTML parser bug</li> |
| 615 | <li>fixed a couple of potentially serious validation bugs</li> |
| 616 | <li>integrated the SGML DocBook support in xmllint</li> |
| 617 | <li>changed the nanoftp anonymous login passwd</li> |
| 618 | <li>some I/O cleanup and a couple of interfaces for Perl wrapper</li> |
| 619 | <li>general bug fixes</li> |
| 620 | <li>updated xmllint man page by John Fleck</li> |
| 621 | <li>some VMS and Windows updates</li> |
| 622 | </ul> |
| 623 | |
Daniel Veillard | 60087f3 | 2001-10-10 09:45:09 +0000 | [diff] [blame] | 624 | <h3>2.4.6: Oct 10 2001</h3> |
| 625 | <ul> |
Daniel Veillard | 52dcab3 | 2001-10-30 12:51:17 +0000 | [diff] [blame] | 626 | <li>added an updated man pages by John Fleck</li> |
Daniel Veillard | 60087f3 | 2001-10-10 09:45:09 +0000 | [diff] [blame] | 627 | <li>portability and configure fixes</li> |
| 628 | <li>an infinite loop on the HTML parser was removed (William)</li> |
| 629 | <li>Windows makefile patches from Igor</li> |
| 630 | <li>fixed half a dozen bugs reported fof libxml or libxslt</li> |
| 631 | <li>updated xmlcatalog to be able to modify SGML super catalogs</li> |
| 632 | </ul> |
| 633 | |
Daniel Veillard | dadd087 | 2001-09-15 09:21:44 +0000 | [diff] [blame] | 634 | <h3>2.4.5: Sep 14 2001</h3> |
| 635 | <ul> |
| 636 | <li>Remove a few annoying bugs in 2.4.4</li> |
| 637 | <li>forces the HTML serializer to output decimal charrefs since some |
| 638 | version of Netscape can't handle hexadecimal ones</li> |
| 639 | </ul> |
| 640 | |
| 641 | <h3>1.8.16: Sep 14 2001</h3> |
| 642 | <ul> |
| 643 | <li>maintenance release of the old libxml1 branch, couple of bug and |
| 644 | portability fixes</li> |
| 645 | </ul> |
| 646 | |
Daniel Veillard | 04382ae | 2001-09-12 18:51:30 +0000 | [diff] [blame] | 647 | <h3>2.4.4: Sep 12 2001</h3> |
| 648 | <ul> |
| 649 | <li>added --convert to xmlcatalog, bug fixes and cleanups of XML |
| 650 | Catalog</li> |
| 651 | <li>a few bug fixes and some portability changes</li> |
| 652 | <li>some documentation cleanups</li> |
| 653 | </ul> |
| 654 | |
Daniel Veillard | 3993690 | 2001-08-24 00:49:01 +0000 | [diff] [blame] | 655 | <h3>2.4.3: Aug 23 2001</h3> |
| 656 | <ul> |
| 657 | <li>XML Catalog support see the doc</li> |
| 658 | <li>New NaN/Infinity floating point code</li> |
| 659 | <li>A few bug fixes</li> |
| 660 | </ul> |
| 661 | |
| 662 | <h3>2.4.2: Aug 15 2001</h3> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 663 | <ul> |
| 664 | <li>adds xmlLineNumbersDefault() to control line number generation</li> |
| 665 | <li>lot of bug fixes</li> |
| 666 | <li>the Microsoft MSC projects files shuld now be up to date</li> |
| 667 | <li>inheritance of namespaces from DTD defaulted attributes</li> |
| 668 | <li>fixes a serious potential security bug</li> |
| 669 | <li>added a --format option to xmllint</li> |
| 670 | </ul> |
| 671 | |
| 672 | <h3>2.4.1: July 24 2001</h3> |
| 673 | <ul> |
| 674 | <li>possibility to keep line numbers in the tree</li> |
| 675 | <li>some computation NaN fixes</li> |
| 676 | <li>extension of the XPath API</li> |
| 677 | <li>cleanup for alpha and ia64 targets</li> |
| 678 | <li>patch to allow saving through HTTP PUT or POST</li> |
Daniel Veillard | 09ab7e1 | 2001-07-10 15:49:44 +0000 | [diff] [blame] | 679 | </ul> |
| 680 | |
| 681 | <h3>2.4.0: July 10 2001</h3> |
| 682 | <ul> |
| 683 | <li>Fixed a few bugs in XPath, validation, and tree handling.</li> |
| 684 | <li>Fixed XML Base implementation, added a coupel of examples to the |
| 685 | regression tests</li> |
| 686 | <li>A bit of cleanup</li> |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 687 | </ul> |
| 688 | |
Daniel Veillard | 5b43fde | 2001-07-05 23:31:40 +0000 | [diff] [blame] | 689 | <h3>2.3.14: July 5 2001</h3> |
| 690 | <ul> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 691 | <li>fixed some entities problems and reduce mem requirement when |
| 692 | substituing them</li> |
Daniel Veillard | 5b43fde | 2001-07-05 23:31:40 +0000 | [diff] [blame] | 693 | <li>lots of improvements in the XPath queries interpreter can be |
| 694 | substancially faster</li> |
| 695 | <li>Makefiles and configure cleanups</li> |
| 696 | <li>Fixes to XPath variable eval, and compare on empty node set</li> |
| 697 | <li>HTML tag closing bug fixed</li> |
| 698 | <li>Fixed an URI reference computating problem when validating</li> |
| 699 | </ul> |
| 700 | |
Daniel Veillard | 2adbb51 | 2001-06-28 16:20:36 +0000 | [diff] [blame] | 701 | <h3>2.3.13: June 28 2001</h3> |
| 702 | <ul> |
| 703 | <li>2.3.12 configure.in was broken as well as the push mode XML parser</li> |
| 704 | <li>a few more fixes for compilation on Windows MSC by Yon Derek</li> |
| 705 | </ul> |
| 706 | |
| 707 | <h3>1.8.14: June 28 2001</h3> |
| 708 | <ul> |
| 709 | <li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li> |
| 710 | <li>Small Makefile fix</li> |
| 711 | </ul> |
| 712 | |
Daniel Veillard | 1164810 | 2001-06-26 16:08:24 +0000 | [diff] [blame] | 713 | <h3>2.3.12: June 26 2001</h3> |
| 714 | <ul> |
| 715 | <li>lots of cleanup</li> |
| 716 | <li>a couple of validation fix</li> |
| 717 | <li>fixed line number counting</li> |
| 718 | <li>fixed serious problems in the XInclude processing</li> |
| 719 | <li>added support for UTF8 BOM at beginning of entities</li> |
| 720 | <li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0 |
| 721 | miscompile uri.c (William), Thomas Leitner provided a fix for the |
| 722 | optimizer on Tru64</li> |
| 723 | <li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for |
| 724 | compilation on Windows MSC</li> |
| 725 | <li>update of libxml-doc.el (Felix Natter)</li> |
| 726 | <li>fixed 2 bugs in URI normalization code</li> |
| 727 | </ul> |
| 728 | |
Daniel Veillard | e3c81b5 | 2001-06-17 14:50:34 +0000 | [diff] [blame] | 729 | <h3>2.3.11: June 17 2001</h3> |
| 730 | <ul> |
| 731 | <li>updates to trio, Makefiles and configure should fix some portability |
| 732 | problems (alpha)</li> |
| 733 | <li>fixed some HTML serialization problems (pre, script, and block/inline |
| 734 | handling), added encoding aware APIs, cleanup of this code</li> |
| 735 | <li>added xmlHasNsProp()</li> |
| 736 | <li>implemented a specific PI for encoding support in the DocBook SGML |
| 737 | parser</li> |
| 738 | <li>some XPath fixes (-Infinity, / as a function parameter and namespaces |
| 739 | node selection)</li> |
| 740 | <li>fixed a performance problem and an error in the validation code</li> |
| 741 | <li>fixed XInclude routine to implement the recursive behaviour</li> |
| 742 | <li>fixed xmlFreeNode problem when libxml is included statically twice</li> |
| 743 | <li>added --version to xmllint for bug reports</li> |
| 744 | </ul> |
| 745 | |
Daniel Veillard | 2e4f188 | 2001-06-01 10:11:57 +0000 | [diff] [blame] | 746 | <h3>2.3.10: June 1 2001</h3> |
| 747 | <ul> |
| 748 | <li>fixed the SGML catalog support</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 749 | <li>a number of reported bugs got fixed, in XPath, iconv detection, |
| 750 | XInclude processing</li> |
Daniel Veillard | 2e4f188 | 2001-06-01 10:11:57 +0000 | [diff] [blame] | 751 | <li>XPath string function should now handle unicode correctly</li> |
| 752 | </ul> |
| 753 | |
Daniel Veillard | 4623acd | 2001-05-19 15:13:15 +0000 | [diff] [blame] | 754 | <h3>2.3.9: May 19 2001</h3> |
| 755 | |
| 756 | <p>Lots of bugfixes, and added a basic SGML catalog support:</p> |
| 757 | <ul> |
| 758 | <li>HTML push bugfix #54891 and another patch from Jonas Borgström</li> |
| 759 | <li>some serious speed optimisation again</li> |
| 760 | <li>some documentation cleanups</li> |
| 761 | <li>trying to get better linking on solaris (-R)</li> |
| 762 | <li>XPath API cleanup from Thomas Broyer</li> |
| 763 | <li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed |
| 764 | xmlValidGetValidElements()</li> |
| 765 | <li>Added an INSTALL file</li> |
| 766 | <li>Attribute removal added to API: #54433</li> |
| 767 | <li>added a basic support for SGML catalogs</li> |
| 768 | <li>fixed xmlKeepBlanksDefault(0) API</li> |
| 769 | <li>bugfix in xmlNodeGetLang()</li> |
| 770 | <li>fixed a small configure portability problem</li> |
| 771 | <li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li> |
| 772 | </ul> |
| 773 | |
Daniel Veillard | a265af7 | 2001-05-14 11:13:58 +0000 | [diff] [blame] | 774 | <h3>1.8.13: May 14 2001</h3> |
| 775 | <ul> |
| 776 | <li>bugfixes release of the old libxml1 branch used by Gnome</li> |
| 777 | </ul> |
| 778 | |
Daniel Veillard | 3bbbe6f | 2001-05-03 11:15:37 +0000 | [diff] [blame] | 779 | <h3>2.3.8: May 3 2001</h3> |
| 780 | <ul> |
| 781 | <li>Integrated an SGML DocBook parser for the Gnome project</li> |
| 782 | <li>Fixed a few things in the HTML parser</li> |
| 783 | <li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating |
| 784 | point portability issue</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 785 | <li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for |
| 786 | DOM+validation using the XML REC as input and a 700MHz celeron).</li> |
Daniel Veillard | 3bbbe6f | 2001-05-03 11:15:37 +0000 | [diff] [blame] | 787 | <li>incorporated more Windows cleanup</li> |
| 788 | <li>added xmlSaveFormatFile()</li> |
| 789 | <li>fixed problems in copying nodes with entities references (gdome)</li> |
| 790 | <li>removed some troubles surrounding the new validation module</li> |
| 791 | </ul> |
| 792 | |
Daniel Veillard | a41123c | 2001-04-22 19:31:20 +0000 | [diff] [blame] | 793 | <h3>2.3.7: April 22 2001</h3> |
| 794 | <ul> |
| 795 | <li>lots of small bug fixes, corrected XPointer</li> |
| 796 | <li>Non determinist content model validation support</li> |
| 797 | <li>added xmlDocCopyNode for gdome2</li> |
| 798 | <li>revamped the way the HTML parser handles end of tags</li> |
| 799 | <li>XPath: corrctions of namespacessupport and number formatting</li> |
| 800 | <li>Windows: Igor Zlatkovic patches for MSC compilation</li> |
| 801 | <li>HTML ouput fixes from P C Chow and William M. Brack</li> |
| 802 | <li>Improved validation speed sensible for DocBook</li> |
| 803 | <li>fixed a big bug with ID declared in external parsed entities</li> |
| 804 | <li>portability fixes, update of Trio from Bjorn Reese</li> |
| 805 | </ul> |
| 806 | |
Daniel Veillard | afc7311 | 2001-04-11 11:51:41 +0000 | [diff] [blame] | 807 | <h3>2.3.6: April 8 2001</h3> |
| 808 | <ul> |
| 809 | <li>Code cleanup using extreme gcc compiler warning options, found and |
| 810 | cleared half a dozen potential problem</li> |
| 811 | <li>the Eazel team found an XML parser bug</li> |
| 812 | <li>cleaned up the user of some of the string formatting function. used the |
| 813 | trio library code to provide the one needed when the platform is missing |
| 814 | them</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 815 | <li>xpath: removed a memory leak and fixed the predicate evaluation |
| 816 | problem, extended the testsuite and cleaned up the result. XPointer seems |
| 817 | broken ...</li> |
Daniel Veillard | afc7311 | 2001-04-11 11:51:41 +0000 | [diff] [blame] | 818 | </ul> |
| 819 | |
Daniel Veillard | 56a4cb8 | 2001-03-24 17:00:36 +0000 | [diff] [blame] | 820 | <h3>2.3.5: Mar 23 2001</h3> |
| 821 | <ul> |
| 822 | <li>Biggest change is separate parsing and evaluation of XPath expressions, |
| 823 | there is some new APIs for this too</li> |
| 824 | <li>included a number of bug fixes(XML push parser, 51876, notations, |
| 825 | 52299)</li> |
| 826 | <li>Fixed some portability issues</li> |
| 827 | </ul> |
| 828 | |
Daniel Veillard | e356c28 | 2001-03-10 12:32:04 +0000 | [diff] [blame] | 829 | <h3>2.3.4: Mar 10 2001</h3> |
| 830 | <ul> |
| 831 | <li>Fixed bugs #51860 and #51861</li> |
| 832 | <li>Added a global variable xmlDefaultBufferSize to allow default buffer |
| 833 | size to be application tunable.</li> |
| 834 | <li>Some cleanup in the validation code, still a bug left and this part |
| 835 | should probably be rewritten to support ambiguous content model :-\</li> |
| 836 | <li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3 |
| 837 | parser</li> |
| 838 | <li>Fixed another bug in xmlNodeGetContent()</li> |
| 839 | <li>Bjorn fixed XPath node collection and Number formatting</li> |
| 840 | <li>Fixed a loop reported in the HTML parsing</li> |
| 841 | <li>blank space are reported even if the Dtd content model proves that they |
| 842 | are formatting spaces, this is for XmL conformance</li> |
| 843 | </ul> |
| 844 | |
Daniel Veillard | b402c07 | 2001-03-01 17:28:58 +0000 | [diff] [blame] | 845 | <h3>2.3.3: Mar 1 2001</h3> |
| 846 | <ul> |
| 847 | <li>small change in XPath for XSLT</li> |
| 848 | <li>documentation cleanups</li> |
| 849 | <li>fix in validation by Gary Pennington</li> |
| 850 | <li>serious parsing performances improvements</li> |
| 851 | </ul> |
| 852 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 853 | <h3>2.3.2: Feb 24 2001</h3> |
Daniel Veillard | 7168110 | 2001-02-24 17:48:53 +0000 | [diff] [blame] | 854 | <ul> |
| 855 | <li>chasing XPath bugs, found a bunch, completed some TODO</li> |
| 856 | <li>fixed a Dtd parsing bug</li> |
| 857 | <li>fixed a bug in xmlNodeGetContent</li> |
| 858 | <li>ID/IDREF support partly rewritten by Gary Pennington</li> |
| 859 | </ul> |
| 860 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 861 | <h3>2.3.1: Feb 15 2001</h3> |
Daniel Veillard | 6e6a6cc | 2001-02-15 15:55:44 +0000 | [diff] [blame] | 862 | <ul> |
| 863 | <li>some XPath and HTML bug fixes for XSLT</li> |
| 864 | <li>small extension of the hash table interfaces for DOM gdome2 |
| 865 | implementation</li> |
| 866 | <li>A few bug fixes</li> |
| 867 | </ul> |
| 868 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 869 | <h3>2.3.0: Feb 8 2001 (2.2.12 was on 25 Jan but I didn't kept track)</h3> |
Daniel Veillard | 6e6a6cc | 2001-02-15 15:55:44 +0000 | [diff] [blame] | 870 | <ul> |
| 871 | <li>Lots of XPath bug fixes</li> |
| 872 | <li>Add a mode with Dtd lookup but without validation error reporting for |
| 873 | XSLT</li> |
| 874 | <li>Add support for text node without escaping (XSLT)</li> |
| 875 | <li>bug fixes for xmlCheckFilename</li> |
| 876 | <li>validation code bug fixes from Gary Pennington</li> |
| 877 | <li>Patch from Paul D. Smith correcting URI path normalization</li> |
| 878 | <li>Patch to allow simultaneous install of libxml-devel and |
| 879 | libxml2-devel</li> |
| 880 | <li>the example Makefile is now fixed</li> |
| 881 | <li>added HTML to the RPM packages</li> |
| 882 | <li>tree copying bugfixes</li> |
| 883 | <li>updates to Windows makefiles</li> |
| 884 | <li>optimisation patch from Bjorn Reese</li> |
| 885 | </ul> |
| 886 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 887 | <h3>2.2.11: Jan 4 2001</h3> |
Daniel Veillard | 503b893 | 2001-01-05 06:36:31 +0000 | [diff] [blame] | 888 | <ul> |
| 889 | <li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li> |
| 890 | <li>added htmlHandleOmittedElem()</li> |
| 891 | <li>Applied Bjorn Reese's IPV6 first patch</li> |
| 892 | <li>Applied Paul D. Smith patches for validation of XInclude results</li> |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 893 | <li>added XPointer xmlns() new scheme support</li> |
Daniel Veillard | 503b893 | 2001-01-05 06:36:31 +0000 | [diff] [blame] | 894 | </ul> |
| 895 | |
Daniel Veillard | 2ddd23d | 2000-11-25 10:42:19 +0000 | [diff] [blame] | 896 | <h3>2.2.10: Nov 25 2000</h3> |
Daniel Veillard | 9d343c4 | 2000-11-25 10:12:43 +0000 | [diff] [blame] | 897 | <ul> |
| 898 | <li>Fix the Windows problems of 2.2.8</li> |
| 899 | <li>integrate OpenVMS patches</li> |
| 900 | <li>better handling of some nasty HTML input</li> |
| 901 | <li>Improved the XPointer implementation</li> |
| 902 | <li>integrate a number of provided patches</li> |
| 903 | </ul> |
| 904 | |
Daniel Veillard | 2ddd23d | 2000-11-25 10:42:19 +0000 | [diff] [blame] | 905 | <h3>2.2.9: Nov 25 2000</h3> |
| 906 | <ul> |
| 907 | <li>erroneous release :-(</li> |
| 908 | </ul> |
| 909 | |
Daniel Veillard | 28929b2 | 2000-11-13 18:22:49 +0000 | [diff] [blame] | 910 | <h3>2.2.8: Nov 13 2000</h3> |
| 911 | <ul> |
| 912 | <li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a> |
| 913 | support</li> |
| 914 | <li>Patch in conditional section handling</li> |
| 915 | <li>updated MS compiler project</li> |
| 916 | <li>fixed some XPath problems</li> |
| 917 | <li>added an URI escaping function</li> |
| 918 | <li>some other bug fixes</li> |
| 919 | </ul> |
| 920 | |
| 921 | <h3>2.2.7: Oct 31 2000</h3> |
| 922 | <ul> |
| 923 | <li>added message redirection</li> |
| 924 | <li>XPath improvements (thanks TOM !)</li> |
| 925 | <li>xmlIOParseDTD() added</li> |
| 926 | <li>various small fixes in the HTML, URI, HTTP and XPointer support</li> |
| 927 | <li>some cleanup of the Makefile, autoconf and the distribution content</li> |
| 928 | </ul> |
| 929 | |
Daniel Veillard | 29a11cc | 2000-10-25 13:32:39 +0000 | [diff] [blame] | 930 | <h3>2.2.6: Oct 25 2000:</h3> |
| 931 | <ul> |
| 932 | <li>Added an hash table module, migrated a number of internal structure to |
| 933 | those</li> |
| 934 | <li>Fixed a posteriori validation problems</li> |
| 935 | <li>HTTP module cleanups</li> |
| 936 | <li>HTML parser improvements (tag errors, script/style handling, attribute |
| 937 | normalization)</li> |
| 938 | <li>coalescing of adjacent text nodes</li> |
| 939 | <li>couple of XPath bug fixes, exported the internal API</li> |
| 940 | </ul> |
| 941 | |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 942 | <h3>2.2.5: Oct 15 2000:</h3> |
Daniel Veillard | 4c3a203 | 1999-11-19 17:46:26 +0000 | [diff] [blame] | 943 | <ul> |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 944 | <li>XPointer implementation and testsuite</li> |
| 945 | <li>Lot of XPath fixes, added variable and functions registration, more |
| 946 | tests</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 947 | <li>Portability fixes, lots of enhancements toward an easy Windows build |
| 948 | and release</li> |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 949 | <li>Late validation fixes</li> |
| 950 | <li>Integrated a lot of contributed patches</li> |
| 951 | <li>added memory management docs</li> |
Daniel Veillard | ab8500d | 2000-10-15 21:06:19 +0000 | [diff] [blame] | 952 | <li>a performance problem when using large buffer seems fixed</li> |
Daniel Veillard | 189446d | 2000-10-13 10:23:06 +0000 | [diff] [blame] | 953 | </ul> |
| 954 | |
| 955 | <h3>2.2.4: Oct 1 2000:</h3> |
| 956 | <ul> |
| 957 | <li>main XPath problem fixed</li> |
| 958 | <li>Integrated portability patches for Windows</li> |
| 959 | <li>Serious bug fixes on the URI and HTML code</li> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 960 | </ul> |
| 961 | |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 962 | <h3>2.2.3: Sep 17 2000</h3> |
| 963 | <ul> |
| 964 | <li>bug fixes</li> |
| 965 | <li>cleanup of entity handling code</li> |
| 966 | <li>overall review of all loops in the parsers, all sprintf usage has been |
| 967 | checked too</li> |
| 968 | <li>Far better handling of larges Dtd. Validating against Docbook XML Dtd |
| 969 | works smoothly now.</li> |
| 970 | </ul> |
| 971 | |
| 972 | <h3>1.8.10: Sep 6 2000</h3> |
| 973 | <ul> |
| 974 | <li>bug fix release for some Gnome projects</li> |
| 975 | </ul> |
| 976 | |
| 977 | <h3>2.2.2: August 12 2000</h3> |
Daniel Veillard | 786d7c8 | 2000-08-12 23:38:57 +0000 | [diff] [blame] | 978 | <ul> |
| 979 | <li>mostly bug fixes</li> |
Daniel Veillard | ec78c0f | 2000-08-25 10:25:23 +0000 | [diff] [blame] | 980 | <li>started adding routines to access xml parser context options</li> |
Daniel Veillard | 786d7c8 | 2000-08-12 23:38:57 +0000 | [diff] [blame] | 981 | </ul> |
| 982 | |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 983 | <h3>2.2.1: July 21 2000</h3> |
Daniel Veillard | a2679fa | 2000-07-22 02:38:15 +0000 | [diff] [blame] | 984 | <ul> |
| 985 | <li>a purely bug fixes release</li> |
| 986 | <li>fixed an encoding support problem when parsing from a memory block</li> |
| 987 | <li>fixed a DOCTYPE parsing problem</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 988 | <li>removed a bug in the function allowing to override the memory |
| 989 | allocation routines</li> |
Daniel Veillard | a2679fa | 2000-07-22 02:38:15 +0000 | [diff] [blame] | 990 | </ul> |
| 991 | |
Daniel Veillard | d5f97f8 | 2000-09-17 16:38:14 +0000 | [diff] [blame] | 992 | <h3>2.2.0: July 14 2000</h3> |
Daniel Veillard | 94e9060 | 2000-07-17 14:38:19 +0000 | [diff] [blame] | 993 | <ul> |
| 994 | <li>applied a lot of portability fixes</li> |
| 995 | <li>better encoding support/cleanup and saving (content is now always |
| 996 | encoded in UTF-8)</li> |
| 997 | <li>the HTML parser now correctly handles encodings</li> |
| 998 | <li>added xmlHasProp()</li> |
| 999 | <li>fixed a serious problem with &#38;</li> |
| 1000 | <li>propagated the fix to FTP client</li> |
| 1001 | <li>cleanup, bugfixes, etc ...</li> |
| 1002 | <li>Added a page about <a href="encoding.html">libxml Internationalization |
| 1003 | support</a></li> |
| 1004 | </ul> |
| 1005 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 1006 | <h3>1.8.9: July 9 2000</h3> |
| 1007 | <ul> |
| 1008 | <li>fixed the spec the RPMs should be better</li> |
| 1009 | <li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve |
| 1010 | rpmfind users problem</li> |
| 1011 | </ul> |
| 1012 | |
Daniel Veillard | 6388e17 | 2000-07-03 16:07:19 +0000 | [diff] [blame] | 1013 | <h3>2.1.1: July 1 2000</h3> |
| 1014 | <ul> |
| 1015 | <li>fixes a couple of bugs in the 2.1.0 packaging</li> |
| 1016 | <li>improvements on the HTML parser</li> |
| 1017 | </ul> |
| 1018 | |
Daniel Veillard | 3f6f7f6 | 2000-06-30 17:58:25 +0000 | [diff] [blame] | 1019 | <h3>2.1.0 and 1.8.8: June 29 2000</h3> |
| 1020 | <ul> |
| 1021 | <li>1.8.8 is mostly a comodity package for upgrading to libxml2 accoding to |
| 1022 | <a href="upgrade.html">new instructions</a>. It fixes a nasty problem |
| 1023 | about &#38; charref parsing</li> |
| 1024 | <li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it |
| 1025 | also contains numerous fixes and enhancements: |
| 1026 | <ul> |
| 1027 | <li>added xmlStopParser() to stop parsing</li> |
| 1028 | <li>improved a lot parsing speed when there is large CDATA blocs</li> |
| 1029 | <li>includes XPath patches provided by Picdar Technology</li> |
| 1030 | <li>tried to fix as much as possible DtD validation and namespace |
| 1031 | related problems</li> |
| 1032 | <li>output to a given encoding has been added/tested</li> |
| 1033 | <li>lot of various fixes</li> |
| 1034 | </ul> |
| 1035 | </li> |
| 1036 | </ul> |
| 1037 | |
Daniel Veillard | e0aed30 | 2000-04-16 08:52:20 +0000 | [diff] [blame] | 1038 | <h3>2.0.0: Apr 12 2000</h3> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 1039 | <ul> |
| 1040 | <li>First public release of libxml2. If you are using libxml, it's a good |
Daniel Veillard | e0aed30 | 2000-04-16 08:52:20 +0000 | [diff] [blame] | 1041 | idea to check the 1.x to 2.x upgrade instructions. NOTE: while initally |
| 1042 | scheduled for Apr 3 the relase occured only on Apr 12 due to massive |
| 1043 | workload.</li> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 1044 | <li>The include are now located under $prefix/include/libxml (instead of |
Daniel Veillard | e0aed30 | 2000-04-16 08:52:20 +0000 | [diff] [blame] | 1045 | $prefix/include/gnome-xml), they also are referenced by |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 1046 | <pre>#include <libxml/xxx.h></pre> |
Daniel Veillard | e0aed30 | 2000-04-16 08:52:20 +0000 | [diff] [blame] | 1047 | <p>instead of</p> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 1048 | <pre>#include "xxx.h"</pre> |
| 1049 | </li> |
Daniel Veillard | 8f62198 | 2000-03-20 13:07:15 +0000 | [diff] [blame] | 1050 | <li>a new URI module for parsing URIs and following strictly RFC 2396</li> |
| 1051 | <li>the memory allocation routines used by libxml can now be overloaded |
| 1052 | dynamically by using xmlMemSetup()</li> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 1053 | <li>The previously CVS only tool tester has been renamed |
| 1054 | <strong>xmllint</strong> and is now installed as part of the libxml2 |
| 1055 | package</li> |
Daniel Veillard | e0aed30 | 2000-04-16 08:52:20 +0000 | [diff] [blame] | 1056 | <li>The I/O interface has been revamped. There is now ways to plug in |
| 1057 | specific I/O modules, either at the URI scheme detection level using |
| 1058 | xmlRegisterInputCallbacks() or by passing I/O functions when creating a |
| 1059 | parser context using xmlCreateIOParserCtxt()</li> |
| 1060 | <li>there is a C preprocessor macro LIBXML_VERSION providing the version |
| 1061 | number of the libxml module in use</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1062 | <li>a number of optional features of libxml can now be excluded at |
| 1063 | configure time (FTP/HTTP/HTML/XPath/Debug)</li> |
Daniel Veillard | edfb29b | 2000-03-14 19:59:05 +0000 | [diff] [blame] | 1064 | </ul> |
| 1065 | |
| 1066 | <h3>2.0.0beta: Mar 14 2000</h3> |
| 1067 | <ul> |
| 1068 | <li>This is a first Beta release of libxml version 2</li> |
Daniel Veillard | e356c28 | 2001-03-10 12:32:04 +0000 | [diff] [blame] | 1069 | <li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org |
| 1070 | FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and |
| 1071 | RPMs</li> |
Daniel Veillard | edfb29b | 2000-03-14 19:59:05 +0000 | [diff] [blame] | 1072 | <li>This version is now the head in the Gnome CVS base, the old one is |
| 1073 | available under the tag LIB_XML_1_X</li> |
| 1074 | <li>This includes a very large set of changes. Froma programmatic point of |
| 1075 | view applications should not have to be modified too much, check the <a |
| 1076 | href="upgrade.html">upgrade page</a></li> |
| 1077 | <li>Some interfaces may changes (especially a bit about encoding).</li> |
| 1078 | <li>the updates includes: |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 1079 | <ul> |
Daniel Veillard | edfb29b | 2000-03-14 19:59:05 +0000 | [diff] [blame] | 1080 | <li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly |
| 1081 | handled now</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1082 | <li>Better handling of entities, especially well formedness checking |
| 1083 | and proper PEref extensions in external subsets</li> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 1084 | <li>DTD conditional sections</li> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1085 | <li>Validation now correcly handle entities content</li> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 1086 | <li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change |
| 1087 | structures to accomodate DOM</a></li> |
Daniel Veillard | 6c8b117 | 2000-03-01 00:40:41 +0000 | [diff] [blame] | 1088 | </ul> |
| 1089 | </li> |
Daniel Veillard | edfb29b | 2000-03-14 19:59:05 +0000 | [diff] [blame] | 1090 | <li>Serious progress were made toward compliance, <a |
| 1091 | href="conf/result.html">here are the result of the test</a> against the |
| 1092 | OASIS testsuite (except the japanese tests since I don't support that |
| 1093 | encoding yet). This URL is rebuilt every couple of hours using the CVS |
| 1094 | head version.</li> |
Daniel Veillard | e41f2b7 | 2000-01-30 20:00:07 +0000 | [diff] [blame] | 1095 | </ul> |
| 1096 | |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1097 | <h3>1.8.7: Mar 6 2000</h3> |
| 1098 | <ul> |
| 1099 | <li>This is a bug fix release:</li> |
| 1100 | <li>It is possible to disable the ignorable blanks heuristic used by |
| 1101 | libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1102 | that for adherence to XML spec, this behaviour will be disabled by |
| 1103 | default in 2.x . The same function will allow to keep compatibility for |
| 1104 | old code.</li> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 1105 | <li>Blanks in <a> </a> constructs are not ignored anymore, |
| 1106 | avoiding heuristic is really the Right Way :-\</li> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1107 | <li>The unchecked use of snprintf which was breaking libxml-1.8.6 |
| 1108 | compilation on some platforms has been fixed</li> |
| 1109 | <li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing |
| 1110 | URIs</li> |
| 1111 | </ul> |
| 1112 | |
Daniel Veillard | e41f2b7 | 2000-01-30 20:00:07 +0000 | [diff] [blame] | 1113 | <h3>1.8.6: Jan 31 2000</h3> |
| 1114 | <ul> |
| 1115 | <li>added a nanoFTP transport module, debugged until the new version of <a |
| 1116 | href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use |
| 1117 | it without troubles</li> |
Daniel Veillard | da07c34 | 2000-01-25 18:31:22 +0000 | [diff] [blame] | 1118 | </ul> |
| 1119 | |
| 1120 | <h3>1.8.5: Jan 21 2000</h3> |
| 1121 | <ul> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 1122 | <li>adding APIs to parse a well balanced chunk of XML (production <a |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1123 | href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the |
| 1124 | XML spec)</li> |
Daniel Veillard | 461a66c | 2000-01-18 18:01:01 +0000 | [diff] [blame] | 1125 | <li>fixed a hideous bug in xmlGetProp pointed by Rune.Djurhuus@fast.no</li> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 1126 | <li>Jody Goldberg <jgoldberg@home.com> provided another patch trying |
| 1127 | to solve the zlib checks problems</li> |
Daniel Veillard | 461a66c | 2000-01-18 18:01:01 +0000 | [diff] [blame] | 1128 | <li>The current state in gnome CVS base is expected to ship as 1.8.5 with |
| 1129 | gnumeric soon</li> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 1130 | </ul> |
| 1131 | |
| 1132 | <h3>1.8.4: Jan 13 2000</h3> |
| 1133 | <ul> |
| 1134 | <li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li> |
| 1135 | <li>all exit() call should have been removed from libxml</li> |
| 1136 | <li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li> |
| 1137 | <li>added newDocFragment()</li> |
Daniel Veillard | f84f71f | 2000-01-05 19:54:23 +0000 | [diff] [blame] | 1138 | </ul> |
| 1139 | |
| 1140 | <h3>1.8.3: Jan 5 2000</h3> |
| 1141 | <ul> |
| 1142 | <li>a Push interface for the XML and HTML parsers</li> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1143 | <li>a shell-like interface to the document tree (try tester --shell :-)</li> |
Daniel Veillard | dbfd641 | 1999-12-28 16:35:14 +0000 | [diff] [blame] | 1144 | <li>lots of bug fixes and improvement added over XMas hollidays</li> |
Daniel Veillard | 437b87b | 2000-01-03 17:30:46 +0000 | [diff] [blame] | 1145 | <li>fixed the DTD parsing code to work with the xhtml DTD</li> |
Daniel Veillard | f84f71f | 2000-01-05 19:54:23 +0000 | [diff] [blame] | 1146 | <li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li> |
| 1147 | <li>Fixed bugs in xmlNewNs()</li> |
Daniel Veillard | 437b87b | 2000-01-03 17:30:46 +0000 | [diff] [blame] | 1148 | <li>External entity loading code has been revamped, now it uses |
Daniel Veillard | f84f71f | 2000-01-05 19:54:23 +0000 | [diff] [blame] | 1149 | xmlLoadExternalEntity(), some fix on entities processing were added</li> |
Daniel Veillard | 437b87b | 2000-01-03 17:30:46 +0000 | [diff] [blame] | 1150 | <li>cleaned up WIN32 includes of socket stuff</li> |
Daniel Veillard | 5cb5ab8 | 1999-12-21 15:35:29 +0000 | [diff] [blame] | 1151 | </ul> |
| 1152 | |
| 1153 | <h3>1.8.2: Dec 21 1999</h3> |
| 1154 | <ul> |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 1155 | <li>I got another problem with includes and C++, I hope this issue is fixed |
| 1156 | for good this time</li> |
Daniel Veillard | 5cb5ab8 | 1999-12-21 15:35:29 +0000 | [diff] [blame] | 1157 | <li>Added a few tree modification functions: xmlReplaceNode, |
| 1158 | xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and |
| 1159 | xmlDocSetRootElement</li> |
| 1160 | <li>Tried to improve the HTML output with help from <a |
| 1161 | href="mailto:clahey@umich.edu">Chris Lahey</a></li> |
Daniel Veillard | e4e5131 | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 1162 | </ul> |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 1163 | |
Daniel Veillard | e4e5131 | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 1164 | <h3>1.8.1: Dec 18 1999</h3> |
| 1165 | <ul> |
| 1166 | <li>various patches to avoid troubles when using libxml with C++ compilers |
| 1167 | the "namespace" keyword and C escaping in include files</li> |
| 1168 | <li>a problem in one of the core macros IS_CHAR was corrected</li> |
| 1169 | <li>fixed a bug introduced in 1.8.0 breaking default namespace processing, |
| 1170 | and more specifically the Dia application</li> |
Daniel Veillard | 944b5ff | 1999-12-15 19:08:24 +0000 | [diff] [blame] | 1171 | <li>fixed a posteriori validation (validation after parsing, or by using a |
| 1172 | Dtd not specified in the original document)</li> |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 1173 | <li>fixed a bug in</li> |
Daniel Veillard | 10a2c65 | 1999-12-12 13:03:50 +0000 | [diff] [blame] | 1174 | </ul> |
| 1175 | |
| 1176 | <h3>1.8.0: Dec 12 1999</h3> |
| 1177 | <ul> |
| 1178 | <li>cleanup, especially memory wise</li> |
| 1179 | <li>the parser should be more reliable, especially the HTML one, it should |
| 1180 | not crash, whatever the input !</li> |
| 1181 | <li>Integrated various patches, especially a speedup improvement for large |
| 1182 | dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>, |
| 1183 | configure with --with-buffers to enable them.</li> |
| 1184 | <li>attribute normalization, oops should have been added long ago !</li> |
| 1185 | <li>attributes defaulted from Dtds should be available, xmlSetProp() now |
| 1186 | does entities escapting by default.</li> |
Daniel Veillard | 4c3a203 | 1999-11-19 17:46:26 +0000 | [diff] [blame] | 1187 | </ul> |
Daniel Veillard | 3500838 | 1999-10-25 13:15:52 +0000 | [diff] [blame] | 1188 | |
| 1189 | <h3>1.7.4: Oct 25 1999</h3> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1190 | <ul> |
Daniel Veillard | 3500838 | 1999-10-25 13:15:52 +0000 | [diff] [blame] | 1191 | <li>Lots of HTML improvement</li> |
| 1192 | <li>Fixed some errors when saving both XML and HTML</li> |
| 1193 | <li>More examples, the regression tests should now look clean</li> |
| 1194 | <li>Fixed a bug with contiguous charref</li> |
| 1195 | </ul> |
| 1196 | |
| 1197 | <h3>1.7.3: Sep 29 1999</h3> |
| 1198 | <ul> |
| 1199 | <li>portability problems fixed</li> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1200 | <li>snprintf was used unconditionnally, leading to link problems on system |
Daniel Veillard | 3500838 | 1999-10-25 13:15:52 +0000 | [diff] [blame] | 1201 | were it's not available, fixed</li> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1202 | </ul> |
| 1203 | |
| 1204 | <h3>1.7.1: Sep 24 1999</h3> |
| 1205 | <ul> |
| 1206 | <li>The basic type for strings manipulated by libxml has been renamed in |
| 1207 | 1.7.1 from <strong>CHAR</strong> to <strong>xmlChar</strong>. The reason |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1208 | is that CHAR was conflicting with a predefined type on Windows. However |
| 1209 | on non WIN32 environment, compatibility is provided by the way of a |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1210 | <strong>#define </strong>.</li> |
| 1211 | <li>Changed another error : the use of a structure field called errno, and |
| 1212 | leading to troubles on platforms where it's a macro</li> |
| 1213 | </ul> |
| 1214 | |
| 1215 | <h3>1.7.0: sep 23 1999</h3> |
| 1216 | <ul> |
| 1217 | <li>Added the ability to fetch remote DTD or parsed entities, see the <a |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 1218 | href="html/libxml-nanohttp.html">nanohttp</a> module.</li> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1219 | <li>Added an errno to report errors by another mean than a simple printf |
| 1220 | like callback</li> |
| 1221 | <li>Finished ID/IDREF support and checking when validation</li> |
| 1222 | <li>Serious memory leaks fixed (there is now a <a |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 1223 | href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li> |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1224 | <li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a> |
| 1225 | implementation</li> |
| 1226 | <li>Added an HTML parser front-end</li> |
| 1227 | </ul> |
| 1228 | |
| 1229 | <h2><a name="XML">XML</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1230 | |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1231 | <p><a href="http://www.w3.org/TR/REC-xml">XML is a standard</a> for |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1232 | markup-based structured documents. Here is <a name="example">an example XML |
| 1233 | document</a>:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 1234 | <pre><?xml version="1.0"?> |
| 1235 | <EXAMPLE prop1="gnome is great" prop2="&amp; linux too"> |
| 1236 | <head> |
| 1237 | <title>Welcome to Gnome</title> |
| 1238 | </head> |
| 1239 | <chapter> |
| 1240 | <title>The Linux adventure</title> |
| 1241 | <p>bla bla bla ...</p> |
| 1242 | <image href="linus.gif"/> |
| 1243 | <p>...</p> |
| 1244 | </chapter> |
| 1245 | </EXAMPLE></pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 1246 | |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1247 | <p>The first line specifies that it's an XML document and gives useful |
| 1248 | information about its encoding. Then the document is a text format whose |
| 1249 | structure is specified by tags between brackets. <strong>Each tag opened has |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1250 | to be closed</strong>. XML is pedantic about this. However, if a tag is empty |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1251 | (no content), a single tag can serve as both the opening and closing tag if |
| 1252 | it ends with <code>/></code> rather than with <code>></code>. Note |
| 1253 | that, for example, the image tag has no content (just an attribute) and is |
| 1254 | closed by ending the tag with <code>/></code>.</p> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 1255 | |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1256 | <p>XML can be applied sucessfully to a wide range of uses, from long term |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1257 | structured document maintenance (where it follows the steps of SGML) to |
| 1258 | simple data encoding mechanisms like configuration file formatting (glade), |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1259 | spreadsheets (gnumeric), or even shorter lived documents such as WebDAV where |
| 1260 | it is used to encode remote calls between a client and a server.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1261 | |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 1262 | <h2><a name="XSLT">XSLT</a></h2> |
| 1263 | |
Daniel Veillard | 6e6a6cc | 2001-02-15 15:55:44 +0000 | [diff] [blame] | 1264 | <p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p> |
| 1265 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1266 | <p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a |
| 1267 | language for transforming XML documents into other XML documents (or |
| 1268 | HTML/textual output).</p> |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 1269 | |
| 1270 | <p>A separate library called libxslt is being built on top of libxml2. This |
| 1271 | module "libxslt" can be found in the Gnome CVS base too.</p> |
| 1272 | |
Daniel Veillard | 383b147 | 2001-01-23 11:39:52 +0000 | [diff] [blame] | 1273 | <p>You can check the <a |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1274 | href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a> |
| 1275 | supported and the progresses on the <a |
Daniel Veillard | 8268716 | 2001-01-22 15:32:01 +0000 | [diff] [blame] | 1276 | href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog">Changelog</a></p> |
| 1277 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 1278 | <h2><a name="architecture">libxml architecture</a></h2> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1279 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 1280 | <p>Libxml is made of multiple components; some of them are optional, and most |
| 1281 | of the block interfaces are public. The main components are:</p> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1282 | <ul> |
| 1283 | <li>an Input/Output layer</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1284 | <li>FTP and HTTP client layers (optional)</li> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1285 | <li>an Internationalization layer managing the encodings support</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1286 | <li>a URI module</li> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1287 | <li>the XML parser and its basic SAX interface</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1288 | <li>an HTML parser using the same SAX interface (optional)</li> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1289 | <li>a SAX tree module to build an in-memory DOM representation</li> |
| 1290 | <li>a tree module to manipulate the DOM representation</li> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1291 | <li>a validation module using the DOM representation (optional)</li> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1292 | <li>an XPath module for global lookup in a DOM representation |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1293 | (optional)</li> |
| 1294 | <li>a debug module (optional)</li> |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1295 | </ul> |
| 1296 | |
| 1297 | <p>Graphically this gives the following:</p> |
| 1298 | |
| 1299 | <p><img src="libxml.gif" alt="a graphical view of the various"></p> |
| 1300 | |
| 1301 | <p></p> |
| 1302 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1303 | <h2><a name="tree">The tree output</a></h2> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 1304 | |
| 1305 | <p>The parser returns a tree built during the document analysis. The value |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1306 | returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1307 | <strong>xmlDoc</strong> structure). This structure contains information such |
Daniel Veillard | 306be99 | 2000-07-03 12:38:45 +0000 | [diff] [blame] | 1308 | as the file name, the document type, and a <strong>children</strong> pointer |
| 1309 | which is the root of the document (or more exactly the first child under the |
| 1310 | root which is the document). The tree is made of <strong>xmlNode</strong>s, |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1311 | chained in double-linked lists of siblings and with a children<->parent |
Daniel Veillard | 306be99 | 2000-07-03 12:38:45 +0000 | [diff] [blame] | 1312 | relationship. An xmlNode can also carry properties (a chain of xmlAttr |
| 1313 | structures). An attribute may have a value which is a list of TEXT or |
| 1314 | ENTITY_REF nodes.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 1315 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1316 | <p>Here is an example (erroneous with respect to the XML spec since there |
| 1317 | should be only one ELEMENT under the root):</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 1318 | |
| 1319 | <p><img src="structure.gif" alt=" structure.gif "></p> |
| 1320 | |
| 1321 | <p>In the source package there is a small program (not installed by default) |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 1322 | called <strong>xmllint</strong> which parses XML files given as argument and |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1323 | prints them back as parsed. This is useful for detecting errors both in XML |
| 1324 | code and in the XML parser itself. It has an option <strong>--debug</strong> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 1325 | which prints the actual in-memory structure of the document; here is the |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 1326 | result with the <a href="#example">example</a> given before:</p> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 1327 | <pre>DOCUMENT |
| 1328 | version=1.0 |
| 1329 | standalone=true |
| 1330 | ELEMENT EXAMPLE |
| 1331 | ATTRIBUTE prop1 |
| 1332 | TEXT |
| 1333 | content=gnome is great |
| 1334 | ATTRIBUTE prop2 |
| 1335 | ENTITY_REF |
| 1336 | TEXT |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 1337 | content= linux too |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1338 | ELEMENT head |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 1339 | ELEMENT title |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 1340 | TEXT |
| 1341 | content=Welcome to Gnome |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 1342 | ELEMENT chapter |
| 1343 | ELEMENT title |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 1344 | TEXT |
| 1345 | content=The Linux adventure |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 1346 | ELEMENT p |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 1347 | TEXT |
| 1348 | content=bla bla bla ... |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 1349 | ELEMENT image |
| 1350 | ATTRIBUTE href |
| 1351 | TEXT |
| 1352 | content=linus.gif |
| 1353 | ELEMENT p |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 1354 | TEXT |
| 1355 | content=...</pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 1356 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1357 | <p>This should be useful for learning the internal representation model.</p> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 1358 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 1359 | <h2><a name="interface">The SAX interface</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1360 | |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1361 | <p>Sometimes the DOM tree output is just too large to fit reasonably into |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1362 | memory. In that case (and if you don't expect to save back the XML document |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 1363 | loaded using libxml), it's better to use the SAX interface of libxml. SAX is |
| 1364 | a <strong>callback-based interface</strong> to the parser. Before parsing, |
| 1365 | the application layer registers a customized set of callbacks which are |
| 1366 | called by the library as it progresses through the XML input.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1367 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1368 | <p>To get more detailed step-by-step guidance on using the SAX interface of |
Daniel Veillard | 4540be4 | 2000-08-19 16:40:28 +0000 | [diff] [blame] | 1369 | libxml, see the <a |
| 1370 | href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice |
| 1371 | documentation</a>.written by <a href="mailto:james@daa.com.au">James |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1372 | Henstridge</a>.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1373 | |
| 1374 | <p>You can debug the SAX behaviour by using the <strong>testSAX</strong> |
| 1375 | program located in the gnome-xml module (it's usually not shipped in the |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1376 | binary packages of libxml, but you can find it in the tar source |
Daniel Veillard | 402e8c8 | 2000-02-29 22:57:47 +0000 | [diff] [blame] | 1377 | distribution). Here is the sequence of callbacks that would be reported by |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 1378 | testSAX when parsing the example XML document shown earlier:</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1379 | <pre>SAX.setDocumentLocator() |
| 1380 | SAX.startDocument() |
| 1381 | SAX.getEntity(amp) |
| 1382 | SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp; linux too') |
| 1383 | SAX.characters( , 3) |
| 1384 | SAX.startElement(head) |
| 1385 | SAX.characters( , 4) |
| 1386 | SAX.startElement(title) |
| 1387 | SAX.characters(Welcome to Gnome, 16) |
| 1388 | SAX.endElement(title) |
| 1389 | SAX.characters( , 3) |
| 1390 | SAX.endElement(head) |
| 1391 | SAX.characters( , 3) |
| 1392 | SAX.startElement(chapter) |
| 1393 | SAX.characters( , 4) |
| 1394 | SAX.startElement(title) |
| 1395 | SAX.characters(The Linux adventure, 19) |
| 1396 | SAX.endElement(title) |
| 1397 | SAX.characters( , 4) |
| 1398 | SAX.startElement(p) |
| 1399 | SAX.characters(bla bla bla ..., 15) |
| 1400 | SAX.endElement(p) |
| 1401 | SAX.characters( , 4) |
| 1402 | SAX.startElement(image, href='linus.gif') |
| 1403 | SAX.endElement(image) |
| 1404 | SAX.characters( , 4) |
| 1405 | SAX.startElement(p) |
| 1406 | SAX.characters(..., 3) |
| 1407 | SAX.endElement(p) |
| 1408 | SAX.characters( , 3) |
| 1409 | SAX.endElement(chapter) |
| 1410 | SAX.characters( , 1) |
| 1411 | SAX.endElement(EXAMPLE) |
| 1412 | SAX.endDocument()</pre> |
| 1413 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 1414 | <p>Most of the other interfaces of libxml are based on the DOM tree-building |
| 1415 | facility, so nearly everything up to the end of this document presupposes the |
| 1416 | use of the standard DOM tree build. Note that the DOM tree itself is built by |
| 1417 | a set of registered default callbacks, without internal specific |
| 1418 | interface.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 1419 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 1420 | <h2><a name="Validation">Validation & DTDs</a></h2> |
| 1421 | |
| 1422 | <p>Table of Content:</p> |
| 1423 | <ol> |
| 1424 | <li><a href="#General5">General overview</a></li> |
| 1425 | <li><a href="#definition">The definition</a></li> |
| 1426 | <li><a href="#Simple">Simple rules</a> |
| 1427 | <ol> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 1428 | <li><a href="#reference">How to reference a DTD from a document</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 1429 | <li><a href="#Declaring">Declaring elements</a></li> |
| 1430 | <li><a href="#Declaring1">Declaring attributes</a></li> |
| 1431 | </ol> |
| 1432 | </li> |
| 1433 | <li><a href="#Some">Some examples</a></li> |
| 1434 | <li><a href="#validate">How to validate</a></li> |
| 1435 | <li><a href="#Other">Other resources</a></li> |
| 1436 | </ol> |
| 1437 | |
| 1438 | <h3><a name="General5">General overview</a></h3> |
| 1439 | |
| 1440 | <p>Well what is validation and what is a DTD ?</p> |
| 1441 | |
| 1442 | <p>DTD is the acronym for Document Type Definition. This is a description of |
| 1443 | the content for a familly of XML files. This is part of the XML 1.0 |
| 1444 | specification, and alows to describe and check that a given document instance |
| 1445 | conforms to a set of rules detailing its structure and content.</p> |
| 1446 | |
| 1447 | <p>Validation is the process of checking a document against a DTD (more |
| 1448 | generally against a set of construction rules).</p> |
| 1449 | |
| 1450 | <p>The validation process and building DTDs are the two most difficult parts |
| 1451 | of the XML life cycle. Briefly a DTD defines all the possibles element to be |
| 1452 | found within your document, what is the formal shape of your document tree |
| 1453 | (by defining the allowed content of an element, either text, a regular |
| 1454 | expression for the allowed list of children, or mixed content i.e. both text |
| 1455 | and children). The DTD also defines the allowed attributes for all elements |
| 1456 | and the types of the attributes.</p> |
| 1457 | |
| 1458 | <h3><a name="definition1">The definition</a></h3> |
| 1459 | |
| 1460 | <p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a |
| 1461 | href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of |
| 1462 | Rev1</a>):</p> |
| 1463 | <ul> |
| 1464 | <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring |
| 1465 | elements</a></li> |
| 1466 | <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring |
| 1467 | attributes</a></li> |
| 1468 | </ul> |
| 1469 | |
| 1470 | <p>(unfortunately) all this is inherited from the SGML world, the syntax is |
| 1471 | ancient...</p> |
| 1472 | |
| 1473 | <h3><a name="Simple1">Simple rules</a></h3> |
| 1474 | |
| 1475 | <p>Writing DTD can be done in multiple ways, the rules to build them if you |
| 1476 | need something fixed or something which can evolve over time can be radically |
| 1477 | different. Really complex DTD like Docbook ones are flexible but quite harder |
| 1478 | to design. I will just focuse on DTDs for a formats with a fixed simple |
| 1479 | structure. It is just a set of basic rules, and definitely not exhaustive nor |
| 1480 | useable for complex DTD design.</p> |
| 1481 | |
| 1482 | <h4><a name="reference1">How to reference a DTD from a document</a>:</h4> |
| 1483 | |
| 1484 | <p>Assuming the top element of the document is <code>spec</code> and the dtd |
| 1485 | is placed in the file <code>mydtd</code> in the subdirectory |
| 1486 | <code>dtds</code> of the directory from where the document were loaded:</p> |
| 1487 | |
| 1488 | <p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p> |
| 1489 | |
| 1490 | <p>Notes:</p> |
| 1491 | <ul> |
| 1492 | <li>the system string is actually an URI-Reference (as defined in <a |
| 1493 | href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a |
| 1494 | full URL string indicating the location of your DTD on the Web, this is a |
| 1495 | really good thing to do if you want others to validate your document</li> |
| 1496 | <li>it is also possible to associate a <code>PUBLIC</code> identifier (a |
| 1497 | magic string) so that the DTd is looked up in catalogs on the client side |
| 1498 | without having to locate it on the web</li> |
| 1499 | <li>a dtd contains a set of elements and attributes declarations, but they |
| 1500 | don't define what the root of the document should be. This is explicitely |
| 1501 | told to the parser/validator as the first element of the |
| 1502 | <code>DOCTYPE</code> declaration.</li> |
| 1503 | </ul> |
| 1504 | |
| 1505 | <h4><a name="Declaring2">Declaring elements</a>:</h4> |
| 1506 | |
| 1507 | <p>The following declares an element <code>spec</code>:</p> |
| 1508 | |
| 1509 | <p><code><!ELEMENT spec (front, body, back?)></code></p> |
| 1510 | |
| 1511 | <p>it also expresses that the spec element contains one <code>front</code>, |
| 1512 | one <code>body</code> and one optionnal <code>back</code> children elements |
| 1513 | in this order. The declaration of one element of the structure and its |
| 1514 | content are done in a single declaration. Similary the following declares |
| 1515 | <code>div1</code> elements:</p> |
| 1516 | |
| 1517 | <p><code><!ELEMENT div1 (head, (p | list | note)*, div2*)></code></p> |
| 1518 | |
| 1519 | <p>means div1 contains one <code>head</code> then a series of optional |
| 1520 | <code>p</code>, <code>list</code>s and <code>note</code>s and then an |
| 1521 | optional <code>div2</code>. And last but not least an element can contain |
| 1522 | text:</p> |
| 1523 | |
| 1524 | <p><code><!ELEMENT b (#PCDATA)></code></p> |
| 1525 | |
| 1526 | <p><code>b</code> contains text or being of mixed content (text and elements |
| 1527 | in no particular order):</p> |
| 1528 | |
| 1529 | <p><code><!ELEMENT p (#PCDATA|a|ul|b|i|em)*></code></p> |
| 1530 | |
| 1531 | <p><code>p </code>can contain text or <code>a</code>, <code>ul</code>, |
| 1532 | <code>b</code>, <code>i </code>or <code>em</code> elements in no particular |
| 1533 | order.</p> |
| 1534 | |
| 1535 | <h4><a name="Declaring1">Declaring attributes</a>:</h4> |
| 1536 | |
| 1537 | <p>again the attributes declaration includes their content definition:</p> |
| 1538 | |
| 1539 | <p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p> |
| 1540 | |
| 1541 | <p>means that the element <code>termdef</code> can have a <code>name</code> |
| 1542 | attribute containing text (<code>CDATA</code>) and which is optionnal |
| 1543 | (<code>#IMPLIED</code>). The attribute value can also be defined within a |
| 1544 | set:</p> |
| 1545 | |
| 1546 | <p><code><!ATTLIST list type (bullets|ordered|glossary) |
| 1547 | "ordered"></code></p> |
| 1548 | |
| 1549 | <p>means <code>list</code> element have a <code>type</code> attribute with 3 |
| 1550 | allowed values "bullets", "ordered" or "glossary" and which default to |
| 1551 | "ordered" if the attribute is not explicitely specified.</p> |
| 1552 | |
| 1553 | <p>The content type of an attribute can be text (<code>CDATA</code>), |
| 1554 | anchor/reference/references |
| 1555 | (<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies) |
| 1556 | (<code>ENTITY</code>/<code>ENTITIES</code>) or name(s) |
| 1557 | (<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a |
| 1558 | <code>chapter</code> element can have an optional <code>id</code> attribute |
| 1559 | of type <code>ID</code>, usable for reference from attribute of type |
| 1560 | IDREF:</p> |
| 1561 | |
| 1562 | <p><code><!ATTLIST chapter id ID #IMPLIED></code></p> |
| 1563 | |
| 1564 | <p>The last value of an attribute definition can be <code>#REQUIRED |
| 1565 | </code>meaning that the attribute has to be given, <code>#IMPLIED</code> |
| 1566 | meaning that it is optional, or the default value (possibly prefixed by |
| 1567 | <code>#FIXED</code> if it is the only allowed).</p> |
| 1568 | |
| 1569 | <p>Notes:</p> |
| 1570 | <ul> |
| 1571 | <li>usually the attributes pertaining to a given element are declared in a |
| 1572 | single expression, but it is just a convention adopted by a lot of DTD |
| 1573 | writers: |
| 1574 | <pre><!ATTLIST termdef |
| 1575 | id ID #REQUIRED |
| 1576 | name CDATA #IMPLIED></pre> |
| 1577 | <p>The previous construct defines both <code>id</code> and |
| 1578 | <code>name</code> attributes for the element <code>termdef</code></p> |
| 1579 | </li> |
| 1580 | </ul> |
| 1581 | |
| 1582 | <h3><a name="Some1">Some examples</a></h3> |
| 1583 | |
| 1584 | <p>The directory <code>test/valid/dtds/</code> in the libxml distribution |
| 1585 | contains some complex DTD examples. The <code>test/valid/dia.xml</code> |
| 1586 | example shows an XML file where the simple DTD is directly included within |
| 1587 | the document.</p> |
| 1588 | |
| 1589 | <h3><a name="validate1">How to validate</a></h3> |
| 1590 | |
| 1591 | <p>The simplest is to use the xmllint program comming with libxml. The |
| 1592 | <code>--valid</code> option turn on validation of the files given as input, |
| 1593 | for example the following validates a copy of the first revision of the XML |
| 1594 | 1.0 specification:</p> |
| 1595 | |
| 1596 | <p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p> |
| 1597 | |
| 1598 | <p>the -- noout is used to not output the resulting tree.</p> |
| 1599 | |
| 1600 | <p>The <code>--dtdvalid dtd</code> allows to validate the document(s) against |
| 1601 | a given DTD.</p> |
| 1602 | |
| 1603 | <p>Libxml exports an API to handle DTDs and validation, check the <a |
| 1604 | href="http://xmlsoft.org/html/libxml-valid.html">associated |
| 1605 | description</a>.</p> |
| 1606 | |
| 1607 | <h3><a name="Other1">Other resources</a></h3> |
| 1608 | |
| 1609 | <p>DTDs are as old as SGML. So there may be a number of examples on-line, I |
| 1610 | will just list one for now, others pointers welcome:</p> |
| 1611 | <ul> |
| 1612 | <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li> |
| 1613 | </ul> |
| 1614 | |
| 1615 | <p>I suggest looking at the examples found under test/valid/dtd and any of |
| 1616 | the large number of books available on XML. The dia example in test/valid |
| 1617 | should be both simple and complete enough to allow you to build your own.</p> |
| 1618 | |
| 1619 | <p></p> |
| 1620 | |
| 1621 | <h2><a name="Memory">Memory Management</a></h2> |
| 1622 | |
| 1623 | <p>Table of Content:</p> |
| 1624 | <ol> |
| 1625 | <li><a href="#General3">General overview</a></li> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 1626 | <li><a href="#setting">Setting libxml set of memory routines</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 1627 | <li><a href="#cleanup">Cleaning up after parsing</a></li> |
| 1628 | <li><a href="#Debugging">Debugging routines</a></li> |
| 1629 | <li><a href="#General4">General memory requirements</a></li> |
| 1630 | </ol> |
| 1631 | |
| 1632 | <h3><a name="General3">General overview</a></h3> |
| 1633 | |
| 1634 | <p>The module <code><a |
| 1635 | href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code> |
| 1636 | provides the interfaces to the libxml memory system:</p> |
| 1637 | <ul> |
| 1638 | <li>libxml does not use the libc memory allocator directly but xmlFree(), |
| 1639 | xmlMalloc() and xmlRealloc()</li> |
| 1640 | <li>those routines can be reallocated to a specific set of routine, by |
| 1641 | default the libc ones i.e. free(), malloc() and realloc()</li> |
| 1642 | <li>the xmlmemory.c module includes a set of debugging routine</li> |
| 1643 | </ul> |
| 1644 | |
| 1645 | <h3><a name="setting">Setting libxml set of memory routines</a></h3> |
| 1646 | |
| 1647 | <p>It is sometimes useful to not use the default memory allocator, either for |
| 1648 | debugging, analysis or to implement a specific behaviour on memory management |
| 1649 | (like on embedded systems). Two function calls are available to do so:</p> |
| 1650 | <ul> |
| 1651 | <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet ()</a> |
| 1652 | which return the current set of functions in use by the parser</li> |
| 1653 | <li><a |
| 1654 | href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a> |
| 1655 | which allow to set up a new set of memory allocation functions</li> |
| 1656 | </ul> |
| 1657 | |
| 1658 | <p>Of course a call to xmlMemSetup() should probably be done before calling |
| 1659 | any other libxml routines (unless you are sure your allocations routines are |
| 1660 | compatibles).</p> |
| 1661 | |
| 1662 | <h3><a name="cleanup">Cleaning up after parsing</a></h3> |
| 1663 | |
| 1664 | <p>Libxml is not stateless, there is a few set of memory structures needing |
| 1665 | allocation before the parser is fully functionnal (some encoding structures |
| 1666 | for example). This also mean that once parsing is finished there is a tiny |
| 1667 | amount of memory (a few hundred bytes) which can be recollected if you don't |
| 1668 | reuse the parser immediately:</p> |
| 1669 | <ul> |
| 1670 | <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser |
| 1671 | ()</a> |
| 1672 | is a centralized routine to free the parsing states. Note that it won't |
| 1673 | deallocate any produced tree if any (use the xmlFreeDoc() and related |
| 1674 | routines for this).</li> |
| 1675 | <li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser |
| 1676 | ()</a> |
| 1677 | is the dual routine allowing to preallocate the parsing state which can |
| 1678 | be useful for example to avoid initialization reentrancy problems when |
| 1679 | using libxml in multithreaded applications</li> |
| 1680 | </ul> |
| 1681 | |
| 1682 | <p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild |
| 1683 | at the next invocation of parser routines, but be careful of the consequences |
| 1684 | in multithreaded applications.</p> |
| 1685 | |
| 1686 | <h3><a name="Debugging">Debugging routines</a></h3> |
| 1687 | |
| 1688 | <p>When configured using --with-mem-debug flag (off by default), libxml uses |
| 1689 | a set of memory allocation debugging routineskeeping track of all allocated |
| 1690 | blocks and the location in the code where the routine was called. A couple of |
| 1691 | other debugging routines allow to dump the memory allocated infos to a file |
| 1692 | or call a specific routine when a given block number is allocated:</p> |
| 1693 | <ul> |
| 1694 | <li><a |
| 1695 | href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a> |
| 1696 | <a |
| 1697 | href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a> |
| 1698 | and <a |
| 1699 | href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a> |
| 1700 | are the memory debugging replacement allocation routines</li> |
| 1701 | <li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump |
| 1702 | ()</a> |
| 1703 | dumps all the informations about the allocated memory block lefts in the |
| 1704 | <code>.memdump</code> file</li> |
| 1705 | </ul> |
| 1706 | |
| 1707 | <p>When developping libxml memory debug is enabled, the tests programs call |
| 1708 | xmlMemoryDump () and the "make test" regression tests will check for any |
| 1709 | memory leak during the full regression test sequence, this helps a lot |
| 1710 | ensuring that libxml does not leak memory and bullet proof memory |
| 1711 | allocations use (some libc implementations are known to be far too permissive |
| 1712 | resulting in major portability problems!).</p> |
| 1713 | |
| 1714 | <p>If the .memdump reports a leak, it displays the allocation function and |
| 1715 | also tries to give some informations about the content and structure of the |
| 1716 | allocated blocks left. This is sufficient in most cases to find the culprit, |
| 1717 | but not always. Assuming the allocation problem is reproductible, it is |
| 1718 | possible to find more easilly:</p> |
| 1719 | <ol> |
| 1720 | <li>write down the block number xxxx not allocated</li> |
| 1721 | <li>export the environement variable XML_MEM_BREAKPOINT=xxxx</li> |
| 1722 | <li>run the program under a debugger and set a breakpoint on |
| 1723 | xmlMallocBreakpoint() a specific function called when this precise block |
| 1724 | is allocated</li> |
| 1725 | <li>when the breakpoint is reached you can then do a fine analysis of the |
| 1726 | allocation an step to see the condition resulting in the missing |
| 1727 | deallocation.</li> |
| 1728 | </ol> |
| 1729 | |
| 1730 | <p>I used to use a commercial tool to debug libxml memory problems but after |
| 1731 | noticing that it was not detecting memory leaks that simple mechanism was |
| 1732 | used and proved extremely efficient until now.</p> |
| 1733 | |
| 1734 | <h3><a name="General4">General memory requirements</a></h3> |
| 1735 | |
| 1736 | <p>How much libxml memory require ? It's hard to tell in average it depends |
| 1737 | of a number of things:</p> |
| 1738 | <ul> |
| 1739 | <li>the parser itself should work in a fixed amout of memory, except for |
| 1740 | information maintained about the stacks of names and entities locations. |
| 1741 | The I/O and encoding handlers will probably account for a few KBytes. |
| 1742 | This is true for both the XML and HTML parser (though the HTML parser |
| 1743 | need more state).</li> |
| 1744 | <li>If you are generating the DOM tree then memory requirements will grow |
| 1745 | nearly lineary with the size of the data. In general for a balanced |
| 1746 | textual document the internal memory requirement is about 4 times the |
| 1747 | size of the UTF8 serialization of this document (exmple the XML-1.0 |
| 1748 | recommendation is a bit more of 150KBytes and takes 650KBytes of main |
| 1749 | memory when parsed). Validation will add a amount of memory required for |
| 1750 | maintaining the external Dtd state which should be linear with the |
| 1751 | complexity of the content model defined by the Dtd</li> |
| 1752 | <li>If you don't care about the advanced features of libxml like |
| 1753 | validation, DOM, XPath or XPointer, but really need to work fixed memory |
| 1754 | requirements, then the SAX interface should be used.</li> |
| 1755 | </ul> |
| 1756 | |
| 1757 | <p></p> |
| 1758 | |
| 1759 | <h2><a name="Encodings">Encodings support</a></h2> |
| 1760 | |
| 1761 | <p>Table of Content:</p> |
| 1762 | <ol> |
| 1763 | <li><a href="encoding.html#What">What does internationalization support |
| 1764 | mean ?</a></li> |
| 1765 | <li><a href="encoding.html#internal">The internal encoding, how and |
| 1766 | why</a></li> |
| 1767 | <li><a href="encoding.html#implemente">How is it implemented ?</a></li> |
| 1768 | <li><a href="encoding.html#Default">Default supported encodings</a></li> |
| 1769 | <li><a href="encoding.html#extend">How to extend the existing |
| 1770 | support</a></li> |
| 1771 | </ol> |
| 1772 | |
| 1773 | <h3><a name="What">What does internationalization support mean ?</a></h3> |
| 1774 | |
| 1775 | <p>XML was designed from the start to allow the support of any character set |
| 1776 | by using Unicode. Any conformant XML parser has to support the UTF-8 and |
| 1777 | UTF-16 default encodings which can both express the full unicode ranges. UTF8 |
| 1778 | is a variable length encoding whose greatest point are to resuse the same |
| 1779 | emcoding for ASCII and to save space for Western encodings, but it is a bit |
| 1780 | more complex to handle in practice. UTF-16 use 2 bytes per characters (and |
| 1781 | sometimes combines two pairs), it makes implementation easier, but looks a |
| 1782 | bit overkill for Western languages encoding. Moreover the XML specification |
| 1783 | allows document to be encoded in other encodings at the condition that they |
| 1784 | are clearly labelled as such. For example the following is a wellformed XML |
| 1785 | document encoded in ISO-8859 1 and using accentuated letter that we French |
| 1786 | likes for both markup and content:</p> |
| 1787 | <pre><?xml version="1.0" encoding="ISO-8859-1"?> |
| 1788 | <très>là</très></pre> |
| 1789 | |
| 1790 | <p>Having internationalization support in libxml means the foolowing:</p> |
| 1791 | <ul> |
| 1792 | <li>the document is properly parsed</li> |
| 1793 | <li>informations about it's encoding are saved</li> |
| 1794 | <li>it can be modified</li> |
| 1795 | <li>it can be saved in its original encoding</li> |
| 1796 | <li>it can also be saved in another encoding supported by libxml (for |
| 1797 | example straight UTF8 or even an ASCII form)</li> |
| 1798 | </ul> |
| 1799 | |
| 1800 | <p>Another very important point is that the whole libxml API, with the |
| 1801 | exception of a few routines to read with a specific encoding or save to a |
| 1802 | specific encoding, is completely agnostic about the original encoding of the |
| 1803 | document.</p> |
| 1804 | |
| 1805 | <p>It should be noted too that the HTML parser embedded in libxml now obbey |
| 1806 | the same rules too, the following document will be (as of 2.2.2) handled in |
| 1807 | an internationalized fashion by libxml too:</p> |
| 1808 | <pre><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" |
| 1809 | "http://www.w3.org/TR/REC-html40/loose.dtd"> |
| 1810 | <html lang="fr"> |
| 1811 | <head> |
| 1812 | <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"> |
| 1813 | </head> |
| 1814 | <body> |
| 1815 | <p>W3C crée des standards pour le Web.</body> |
| 1816 | </html></pre> |
| 1817 | |
| 1818 | <h3><a name="internal">The internal encoding, how and why</a></h3> |
| 1819 | |
| 1820 | <p>One of the core decision was to force all documents to be converted to a |
| 1821 | default internal encoding, and that encoding to be UTF-8, here are the |
| 1822 | rationale for those choices:</p> |
| 1823 | <ul> |
| 1824 | <li>keeping the native encoding in the internal form would force the libxml |
| 1825 | users (or the code associated) to be fully aware of the encoding of the |
| 1826 | original document, for examples when adding a text node to a document, |
| 1827 | the content would have to be provided in the document encoding, i.e. the |
| 1828 | client code would have to check it before hand, make sure it's conformant |
| 1829 | to the encoding, etc ... Very hard in practice, though in some specific |
| 1830 | cases this may make sense.</li> |
| 1831 | <li>the second decision was which encoding. From the XML spec only UTF8 and |
| 1832 | UTF16 really makes sense as being the two only encodings for which there |
| 1833 | is amndatory support. UCS-4 (32 bits fixed size encoding) could be |
| 1834 | considered an intelligent choice too since it's a direct Unicode mapping |
| 1835 | support. I selected UTF-8 on the basis of efficiency and compatibility |
| 1836 | with surrounding software: |
| 1837 | <ul> |
| 1838 | <li>UTF-8 while a bit more complex to convert from/to (i.e. slightly |
| 1839 | more costly to import and export CPU wise) is also far more compact |
| 1840 | than UTF-16 (and UCS-4) for a majority of the documents I see it used |
| 1841 | for right now (RPM RDF catalogs, advogato data, various configuration |
| 1842 | file formats, etc.) and the key point for today's computer |
| 1843 | architecture is efficient uses of caches. If one nearly double the |
| 1844 | memory requirement to store the same amount of data, this will trash |
| 1845 | caches (main memory/external caches/internal caches) and my take is |
| 1846 | that this harms the system far more than the CPU requirements needed |
| 1847 | for the conversion to UTF-8</li> |
| 1848 | <li>Most of libxml version 1 users were using it with straight ASCII |
| 1849 | most of the time, doing the conversion with an internal encoding |
| 1850 | requiring all their code to be rewritten was a serious show-stopper |
| 1851 | for using UTF-16 or UCS-4.</li> |
| 1852 | <li>UTF-8 is being used as the de-facto internal encoding standard for |
| 1853 | related code like the <a href="http://www.pango.org/">pango</a> |
| 1854 | upcoming Gnome text widget, and a lot of Unix code (yep another place |
| 1855 | where Unix programmer base takes a different approach from Microsoft |
| 1856 | - they are using UTF-16)</li> |
| 1857 | </ul> |
| 1858 | </li> |
| 1859 | </ul> |
| 1860 | |
| 1861 | <p>What does this mean in practice for the libxml user:</p> |
| 1862 | <ul> |
| 1863 | <li>xmlChar, the libxml data type is a byte, those bytes must be assembled |
| 1864 | as UTF-8 valid strings. The proper way to terminate an xmlChar * string |
| 1865 | is simply to append 0 byte, as usual.</li> |
| 1866 | <li>One just need to make sure that when using chars outside the ASCII set, |
| 1867 | the values has been properly converted to UTF-8</li> |
| 1868 | </ul> |
| 1869 | |
| 1870 | <h3><a name="implemente">How is it implemented ?</a></h3> |
| 1871 | |
| 1872 | <p>Let's describe how all this works within libxml, basically the I18N |
| 1873 | (internationalization) support get triggered only during I/O operation, i.e. |
| 1874 | when reading a document or saving one. Let's look first at the reading |
| 1875 | sequence:</p> |
| 1876 | <ol> |
| 1877 | <li>when a document is processed, we usually don't know the encoding, a |
| 1878 | simple heuristic allows to detect UTF-18 and UCS-4 from whose where the |
| 1879 | ASCII range (0-0x7F) maps with ASCII</li> |
| 1880 | <li>the xml declaration if available is parsed, including the encoding |
| 1881 | declaration. At that point, if the autodetected encoding is different |
| 1882 | from the one declared a call to xmlSwitchEncoding() is issued.</li> |
| 1883 | <li>If there is no encoding declaration, then the input has to be in either |
| 1884 | UTF-8 or UTF-16, if it is not then at some point when processing the |
| 1885 | input, the converter/checker of UTF-8 form will raise an encoding error. |
| 1886 | You may end-up with a garbled document, or no document at all ! Example: |
| 1887 | <pre>~/XML -> ./xmllint err.xml |
| 1888 | err.xml:1: error: Input is not proper UTF-8, indicate encoding ! |
| 1889 | <très>là</très> |
| 1890 | ^ |
| 1891 | err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C |
| 1892 | <très>là</très> |
| 1893 | ^</pre> |
| 1894 | </li> |
| 1895 | <li>xmlSwitchEncoding() does an encoding name lookup, canonalize it, and |
| 1896 | then search the default registered encoding converters for that encoding. |
| 1897 | If it's not within the default set and iconv() support has been compiled |
| 1898 | it, it will ask iconv for such an encoder. If this fails then the parser |
| 1899 | will report an error and stops processing: |
| 1900 | <pre>~/XML -> ./xmllint err2.xml |
| 1901 | err2.xml:1: error: Unsupported encoding UnsupportedEnc |
| 1902 | <?xml version="1.0" encoding="UnsupportedEnc"?> |
| 1903 | ^</pre> |
| 1904 | </li> |
| 1905 | <li>From that point the encoder process progressingly the input (it is |
| 1906 | plugged as a front-end to the I/O module) for that entity. It captures |
| 1907 | and convert on-the-fly the document to be parsed to UTF-8. The parser |
| 1908 | itself just does UTF-8 checking of this input and process it |
| 1909 | transparently. The only difference is that the encoding information has |
| 1910 | been added to the parsing context (more precisely to the input |
| 1911 | corresponding to this entity).</li> |
| 1912 | <li>The result (when using DOM) is an internal form completely in UTF-8 |
| 1913 | with just an encoding information on the document node.</li> |
| 1914 | </ol> |
| 1915 | |
| 1916 | <p>Ok then what's happen when saving the document (assuming you |
| 1917 | colllected/built an xmlDoc DOM like structure) ? It depends on the function |
| 1918 | called, xmlSaveFile() will just try to save in the original encoding, while |
| 1919 | xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given |
| 1920 | encoding:</p> |
| 1921 | <ol> |
| 1922 | <li>if no encoding is given, libxml will look for an encoding value |
| 1923 | associated to the document and if it exists will try to save to that |
| 1924 | encoding, |
| 1925 | <p>otherwise everything is written in the internal form, i.e. UTF-8</p> |
| 1926 | </li> |
| 1927 | <li>so if an encoding was specified, either at the API level or on the |
| 1928 | document, libxml will again canonalize the encoding name, lookup for a |
| 1929 | converter in the registered set or through iconv. If not found the |
| 1930 | function will return an error code</li> |
| 1931 | <li>the converter is placed before the I/O buffer layer, as another kind of |
| 1932 | buffer, then libxml will simply push the UTF-8 serialization to through |
| 1933 | that buffer, which will then progressively be converted and pushed onto |
| 1934 | the I/O layer.</li> |
| 1935 | <li>It is possible that the converter code fails on some input, for example |
| 1936 | trying to push an UTF-8 encoded chinese character through the UTF-8 to |
| 1937 | ISO-8859-1 converter won't work. Since the encoders are progressive they |
| 1938 | will just report the error and the number of bytes converted, at that |
| 1939 | point libxml will decode the offending character, remove it from the |
| 1940 | buffer and replace it with the associated charRef encoding &#123; and |
| 1941 | resume the convertion. This guarante that any document will be saved |
| 1942 | without losses (except for markup names where this is not legal, this is |
| 1943 | a problem in the current version, in pactice avoid using non-ascci |
| 1944 | characters for tags or attributes names @@). A special "ascii" encoding |
| 1945 | name is used to save documents to a pure ascii form can be used when |
| 1946 | portability is really crucial</li> |
| 1947 | </ol> |
| 1948 | |
| 1949 | <p>Here is a few examples based on the same test document:</p> |
| 1950 | <pre>~/XML -> ./xmllint isolat1 |
| 1951 | <?xml version="1.0" encoding="ISO-8859-1"?> |
| 1952 | <très>là</très> |
| 1953 | ~/XML -> ./xmllint --encode UTF-8 isolat1 |
| 1954 | <?xml version="1.0" encoding="UTF-8"?> |
| 1955 | <très>là </très> |
| 1956 | ~/XML -> </pre> |
| 1957 | |
| 1958 | <p>The same processing is applied (and reuse most of the code) for HTML I18N |
| 1959 | processing. Looking up and modifying the content encoding is a bit more |
| 1960 | difficult since it is located in a <meta> tag under the <head>, |
| 1961 | so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have |
| 1962 | been provided. The parser also attempts to switch encoding on the fly when |
| 1963 | detecting such a tag on input. Except for that the processing is the same |
| 1964 | (and again reuses the same code).</p> |
| 1965 | |
| 1966 | <h3><a name="Default">Default supported encodings</a></h3> |
| 1967 | |
| 1968 | <p>libxml has a set of default converters for the following encodings |
| 1969 | (located in encoding.c):</p> |
| 1970 | <ol> |
| 1971 | <li>UTF-8 is supported by default (null handlers)</li> |
| 1972 | <li>UTF-16, both little and big endian</li> |
| 1973 | <li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li> |
| 1974 | <li>ASCII, useful mostly for saving</li> |
| 1975 | <li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML |
| 1976 | predefined entities like &copy; for the Copyright sign.</li> |
| 1977 | </ol> |
| 1978 | |
| 1979 | <p>More over when compiled on an Unix platfor with iconv support the full set |
| 1980 | of encodings supported by iconv can be instantly be used by libxml. On a |
| 1981 | linux machine with glibc-2.1 the list of supported encodings and aliases fill |
| 1982 | 3 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the |
| 1983 | various Japanese ones.</p> |
| 1984 | |
| 1985 | <h4>Encoding aliases</h4> |
| 1986 | |
| 1987 | <p>From 2.2.3, libxml has support to register encoding names aliases. The |
| 1988 | goal is to be able to parse document whose encoding is supported but where |
| 1989 | the name differs (for example from the default set of names accepted by |
| 1990 | iconv). The following functions allow to register and handle new aliases for |
| 1991 | existing encodings. Once registered libxml will automatically lookup the |
| 1992 | aliases when handling a document:</p> |
| 1993 | <ul> |
| 1994 | <li>int xmlAddEncodingAlias(const char *name, const char *alias);</li> |
| 1995 | <li>int xmlDelEncodingAlias(const char *alias);</li> |
| 1996 | <li>const char * xmlGetEncodingAlias(const char *alias);</li> |
| 1997 | <li>void xmlCleanupEncodingAliases(void);</li> |
| 1998 | </ul> |
| 1999 | |
| 2000 | <h3><a name="extend">How to extend the existing support</a></h3> |
| 2001 | |
| 2002 | <p>Well adding support for new encoding, or overriding one of the encoders |
| 2003 | (assuming it is buggy) should not be hard, just write an input and output |
| 2004 | conversion routines to/from UTF-8, and register them using |
| 2005 | xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be |
| 2006 | called automatically if the parser(s) encounter such an encoding name |
| 2007 | (register it uppercase, this will help). The description of the encoders, |
| 2008 | their arguments and expected return values are described in the encoding.h |
| 2009 | header.</p> |
| 2010 | |
| 2011 | <p>A quick note on the topic of subverting the parser to use a different |
| 2012 | internal encoding than UTF-8, in some case people will absolutely want to |
| 2013 | keep the internal encoding different, I think it's still possible (but the |
| 2014 | encoding must be compliant with ASCII on the same subrange) though I didn't |
| 2015 | tried it. The key is to override the default conversion routines (by |
| 2016 | registering null encoders/decoders for your charsets), and bypass the UTF-8 |
| 2017 | checking of the parser by setting the parser context charset |
| 2018 | (ctxt->charset) to something different than XML_CHAR_ENCODING_UTF8, but |
| 2019 | there is no guarantee taht this will work. You may also have some troubles |
| 2020 | saving back.</p> |
| 2021 | |
| 2022 | <p>Basically proper I18N support is important, this requires at least |
| 2023 | libxml-2.0.0, but a lot of features and corrections are really available only |
| 2024 | starting 2.2.</p> |
| 2025 | |
| 2026 | <h2><a name="IO">I/O Interfaces</a></h2> |
| 2027 | |
| 2028 | <p>Table of Content:</p> |
| 2029 | <ol> |
| 2030 | <li><a href="#General1">General overview</a></li> |
| 2031 | <li><a href="#basic">The basic buffer type</a></li> |
| 2032 | <li><a href="#Input">Input I/O handlers</a></li> |
| 2033 | <li><a href="#Output">Output I/O handlers</a></li> |
| 2034 | <li><a href="#entities">The entities loader</a></li> |
| 2035 | <li><a href="#Example2">Example of customized I/O</a></li> |
| 2036 | </ol> |
| 2037 | |
| 2038 | <h3><a name="General1">General overview</a></h3> |
| 2039 | |
| 2040 | <p>The module <code><a |
| 2041 | href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides |
| 2042 | the interfaces to the libxml I/O system. This consists of 4 main parts:</p> |
| 2043 | <ul> |
| 2044 | <li>Entities loader, this is a routine which tries to fetch the entities |
| 2045 | (files) based on their PUBLIC and SYSTEM identifiers. The default loader |
| 2046 | don't look at the public identifier since libxml do not maintain a |
| 2047 | catalog. You can redefine you own entity loader by using |
| 2048 | <code>xmlGetExternalEntityLoader()</code> and |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 2049 | <code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the |
| 2050 | example</a>.</li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2051 | <li>Input I/O buffers which are a commodity structure used by the parser(s) |
| 2052 | input layer to handle fetching the informations to feed the parser. This |
| 2053 | provides buffering and is also a placeholder where the encoding |
| 2054 | convertors to UTF8 are piggy-backed.</li> |
| 2055 | <li>Output I/O buffers are similar to the Input ones and fulfill similar |
| 2056 | task but when generating a serialization from a tree.</li> |
| 2057 | <li>A mechanism to register sets of I/O callbacks and associate them with |
| 2058 | specific naming schemes like the protocol part of the URIs. |
| 2059 | <p>This affect the default I/O operations and allows to use specific I/O |
| 2060 | handlers for certain names.</p> |
| 2061 | </li> |
| 2062 | </ul> |
| 2063 | |
| 2064 | <p>The general mechanism used when loading http://rpmfind.net/xml.html for |
| 2065 | example in the HTML parser is the following:</p> |
| 2066 | <ol> |
| 2067 | <li>The default entity loader calls <code>xmlNewInputFromFile()</code> with |
| 2068 | the parsing context and the URI string.</li> |
| 2069 | <li>the URI string is checked against the existing registered handlers |
| 2070 | using their match() callback function, if the HTTP module was compiled |
| 2071 | in, it is registered and its match() function will succeeds</li> |
| 2072 | <li>the open() function of the handler is called and if successful will |
| 2073 | return an I/O Input buffer</li> |
| 2074 | <li>the parser will the start reading from this buffer and progressively |
| 2075 | fetch information from the resource, calling the read() function of the |
| 2076 | handler until the resource is exhausted</li> |
| 2077 | <li>if an encoding change is detected it will be installed on the input |
| 2078 | buffer, providing buffering and efficient use of the conversion |
| 2079 | routines</li> |
| 2080 | <li>once the parser has finished, the close() function of the handler is |
| 2081 | called once and the Input buffer and associed resources are |
| 2082 | deallocated.</li> |
| 2083 | </ol> |
| 2084 | |
| 2085 | <p>The user defined callbacks are checked first to allow overriding of the |
| 2086 | default libxml I/O routines.</p> |
| 2087 | |
| 2088 | <h3><a name="basic">The basic buffer type</a></h3> |
| 2089 | |
| 2090 | <p>All the buffer manipulation handling is done using the |
| 2091 | <code>xmlBuffer</code> type define in <code><a |
| 2092 | href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a |
| 2093 | resizable memory buffer. The buffer allocation strategy can be selected to be |
| 2094 | either best-fit or use an exponential doubling one (CPU vs. memory use |
| 2095 | tradeoff). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and |
| 2096 | <code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a |
| 2097 | system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number |
| 2098 | of functions allows to manipulate buffers with names starting with the |
| 2099 | <code>xmlBuffer...</code> prefix.</p> |
| 2100 | |
| 2101 | <h3><a name="Input">Input I/O handlers</a></h3> |
| 2102 | |
| 2103 | <p>An Input I/O handler is a simple structure |
| 2104 | <code>xmlParserInputBuffer</code> containing a context associated to the |
| 2105 | resource (file descriptor, or pointer to a protocol handler), the read() and |
| 2106 | close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset |
| 2107 | encoding handler are also present to support charset conversion when |
| 2108 | needed.</p> |
| 2109 | |
| 2110 | <h3><a name="Output">Output I/O handlers</a></h3> |
| 2111 | |
| 2112 | <p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an |
| 2113 | Input one except the callbacks are write() and close().</p> |
| 2114 | |
| 2115 | <h3><a name="entities">The entities loader</a></h3> |
| 2116 | |
| 2117 | <p>The entity loader resolves requests for new entities and create inputs for |
| 2118 | the parser. Creating an input from a filename or an URI string is done |
| 2119 | through the xmlNewInputFromFile() routine. The default entity loader do not |
| 2120 | handle the PUBLIC identifier associated with an entity (if any). So it just |
| 2121 | calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in |
| 2122 | XML).</p> |
| 2123 | |
| 2124 | <p>If you want to hook up a catalog mechanism then you simply need to |
| 2125 | override the default entity loader, here is an example:</p> |
| 2126 | <pre>#include <libxml/xmlIO.h> |
| 2127 | |
| 2128 | xmlExternalEntityLoader defaultLoader = NULL; |
| 2129 | |
| 2130 | xmlParserInputPtr |
| 2131 | xmlMyExternalEntityLoader(const char *URL, const char *ID, |
| 2132 | xmlParserCtxtPtr ctxt) { |
| 2133 | xmlParserInputPtr ret; |
| 2134 | const char *fileID = NULL; |
| 2135 | /* lookup for the fileID depending on ID */ |
| 2136 | |
| 2137 | ret = xmlNewInputFromFile(ctxt, fileID); |
| 2138 | if (ret != NULL) |
| 2139 | return(ret); |
| 2140 | if (defaultLoader != NULL) |
| 2141 | ret = defaultLoader(URL, ID, ctxt); |
| 2142 | return(ret); |
| 2143 | } |
| 2144 | |
| 2145 | int main(..) { |
| 2146 | ... |
| 2147 | |
| 2148 | /* |
| 2149 | * Install our own entity loader |
| 2150 | */ |
| 2151 | defaultLoader = xmlGetExternalEntityLoader(); |
| 2152 | xmlSetExternalEntityLoader(xmlMyExternalEntityLoader); |
| 2153 | |
| 2154 | ... |
| 2155 | }</pre> |
| 2156 | |
| 2157 | <h3><a name="Example2">Example of customized I/O</a></h3> |
| 2158 | |
| 2159 | <p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a |
| 2160 | real use case</a>, xmlDocDump() closes the FILE * passed by the application |
| 2161 | and this was a problem. The <a |
| 2162 | href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a |
| 2163 | new output handler with the closing call deactivated:</p> |
| 2164 | <ol> |
| 2165 | <li>First define a new I/O ouput allocator where the output don't close the |
| 2166 | file: |
| 2167 | <pre>xmlOutputBufferPtr |
| 2168 | xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) { |
| 2169 | xmlOutputBufferPtr ret; |
| 2170 | |
| 2171 | if (xmlOutputCallbackInitialized == 0) |
| 2172 | xmlRegisterDefaultOutputCallbacks(); |
| 2173 | |
| 2174 | if (file == NULL) return(NULL); |
| 2175 | ret = xmlAllocOutputBuffer(encoder); |
| 2176 | if (ret != NULL) { |
| 2177 | ret->context = file; |
| 2178 | ret->writecallback = xmlFileWrite; |
| 2179 | ret->closecallback = NULL; /* No close callback */ |
| 2180 | } |
| 2181 | return(ret); <br> |
| 2182 | |
| 2183 | |
| 2184 | |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 2185 | |
| 2186 | |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 2187 | |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 2188 | |
Daniel Veillard | 52dcab3 | 2001-10-30 12:51:17 +0000 | [diff] [blame] | 2189 | |
Daniel Veillard | ed421aa | 2001-11-04 21:22:45 +0000 | [diff] [blame] | 2190 | |
Daniel Veillard | 43d3f61 | 2001-11-10 11:57:23 +0000 | [diff] [blame] | 2191 | |
Daniel Veillard | a487105 | 2001-11-26 13:19:48 +0000 | [diff] [blame] | 2192 | |
Daniel Veillard | 1aadc44 | 2001-11-28 13:10:32 +0000 | [diff] [blame] | 2193 | |
Daniel Veillard | ef90ba7 | 2001-12-07 14:24:22 +0000 | [diff] [blame] | 2194 | |
Daniel Veillard | 9ae4b7a | 2001-12-13 14:24:09 +0000 | [diff] [blame] | 2195 | |
Daniel Veillard | 845cce4 | 2002-01-09 11:51:37 +0000 | [diff] [blame] | 2196 | |
Daniel Veillard | 744683d | 2002-01-14 17:30:20 +0000 | [diff] [blame^] | 2197 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2198 | } </pre> |
| 2199 | </li> |
| 2200 | <li>And then use it to save the document: |
| 2201 | <pre>FILE *f; |
| 2202 | xmlOutputBufferPtr output; |
| 2203 | xmlDocPtr doc; |
| 2204 | int res; |
| 2205 | |
| 2206 | f = ... |
| 2207 | doc = .... |
| 2208 | |
| 2209 | output = xmlOutputBufferCreateOwn(f, NULL); |
| 2210 | res = xmlSaveFileTo(output, doc, NULL); |
| 2211 | </pre> |
| 2212 | </li> |
| 2213 | </ol> |
| 2214 | |
| 2215 | <h2><a name="Catalog">Catalog support</a></h2> |
| 2216 | |
| 2217 | <p>Table of Content:</p> |
| 2218 | <ol> |
| 2219 | <li><a href="General2">General overview</a></li> |
| 2220 | <li><a href="#definition">The definition</a></li> |
| 2221 | <li><a href="#Simple">Using catalogs</a></li> |
| 2222 | <li><a href="#Some">Some examples</a></li> |
| 2223 | <li><a href="#reference">How to tune catalog usage</a></li> |
| 2224 | <li><a href="#validate">How to debug catalog processing</a></li> |
| 2225 | <li><a href="#Declaring">How to create and maintain catalogs</a></li> |
| 2226 | <li><a href="#implemento">The implementor corner quick review of the |
| 2227 | API</a></li> |
| 2228 | <li><a href="#Other">Other resources</a></li> |
| 2229 | </ol> |
| 2230 | |
| 2231 | <h3><a name="General2">General overview</a></h3> |
| 2232 | |
| 2233 | <p>What is a catalog? Basically it's a lookup mechanism used when an entity |
| 2234 | (a file or a remote resource) references another entity. The catalog lookup |
| 2235 | is inserted between the moment the reference is recognized by the software |
| 2236 | (XML parser, stylesheet processing, or even images referenced for inclusion |
| 2237 | in a rendering) and the time where loading that resource is actually |
| 2238 | started.</p> |
| 2239 | |
| 2240 | <p>It is basically used for 3 things:</p> |
| 2241 | <ul> |
| 2242 | <li>mapping from "logical" names, the public identifiers and a more |
| 2243 | concrete name usable for download (and URI). For example it can associate |
| 2244 | the logical name |
| 2245 | <p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p> |
| 2246 | <p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be |
| 2247 | downloaded</p> |
| 2248 | <p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p> |
| 2249 | </li> |
| 2250 | <li>remapping from a given URL to another one, like an HTTP indirection |
| 2251 | saying that |
| 2252 | <p>"http://www.oasis-open.org/committes/tr.xsl"</p> |
| 2253 | <p>should really be looked at</p> |
| 2254 | <p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p> |
| 2255 | </li> |
| 2256 | <li>providing a local cache mechanism allowing to load the entities |
| 2257 | associated to public identifiers or remote resources, this is a really |
| 2258 | important feature for any significant deployment of XML or SGML since it |
| 2259 | allows to avoid the aleas and delays associated to fetching remote |
| 2260 | resources.</li> |
| 2261 | </ul> |
| 2262 | |
| 2263 | <h3><a name="definition">The definitions</a></h3> |
| 2264 | |
| 2265 | <p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p> |
| 2266 | <ul> |
| 2267 | <li>the older SGML catalogs, the official spec is SGML Open Technical |
| 2268 | Resolution TR9401:1997, but is better understood by reading <a |
| 2269 | href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from |
| 2270 | James Clark. This is relatively old and not the preferred mode of |
| 2271 | operation of libxml.</li> |
| 2272 | <li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML |
| 2273 | Catalogs</a> |
| 2274 | is far more flexible, more recent, uses an XML syntax and should scale |
| 2275 | quite better. This is the default option of libxml.</li> |
| 2276 | </ul> |
| 2277 | |
| 2278 | <p></p> |
| 2279 | |
| 2280 | <h3><a name="Simple">Using catalog</a></h3> |
| 2281 | |
| 2282 | <p>In a normal environment libxml will by default check the presence of a |
| 2283 | catalog in /etc/xml/catalog, and assuming it has been correctly populated, |
| 2284 | the processing is completely transparent to the document user. To take a |
| 2285 | concrete example, suppose you are authoring a DocBook document, this one |
| 2286 | starts with the following DOCTYPE definition:</p> |
| 2287 | <pre><?xml version='1.0'?> |
| 2288 | <!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN" |
| 2289 | "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"></pre> |
| 2290 | |
| 2291 | <p>When validating the document with libxml, the catalog will be |
| 2292 | automatically consulted to lookup the public identifier "-//Norman Walsh//DTD |
| 2293 | DocBk XML V3.1.4//EN" and the system identifier |
| 2294 | "http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have |
| 2295 | been installed on your system and the catalogs actually point to them, libxml |
| 2296 | will fetch them from the local disk.</p> |
| 2297 | |
| 2298 | <p style="font-size: 10pt"><strong>Note</strong>: Really don't use this |
| 2299 | DOCTYPE example it's a really old version, but is fine as an example.</p> |
| 2300 | |
| 2301 | <p>Libxml will check the catalog each time that it is requested to load an |
| 2302 | entity, this includes DTD, external parsed entities, stylesheets, etc ... If |
| 2303 | your system is correctly configured all the authoring phase and processing |
| 2304 | should use only local files, even if your document stays portable because it |
| 2305 | uses the canonical public and system ID, referencing the remote document.</p> |
| 2306 | |
| 2307 | <h3><a name="Some">Some examples:</a></h3> |
| 2308 | |
| 2309 | <p>Here is a couple of fragments from XML Catalogs used in libxml early |
| 2310 | regression tests in <code>test/catalogs</code> :</p> |
| 2311 | <pre><?xml version="1.0"?> |
| 2312 | <!DOCTYPE catalog PUBLIC |
| 2313 | "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" |
| 2314 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> |
| 2315 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"> |
| 2316 | <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2317 | uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/> |
| 2318 | ...</pre> |
| 2319 | |
| 2320 | <p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are |
| 2321 | written in XML, there is a specific namespace for catalog elements |
| 2322 | "urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this |
| 2323 | catalog is a <code>public</code> mapping it allows to associate a Public |
| 2324 | Identifier with an URI.</p> |
| 2325 | <pre>... |
| 2326 | <rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/" |
| 2327 | rewritePrefix="file:///usr/share/xml/docbook/"/> |
| 2328 | ...</pre> |
| 2329 | |
| 2330 | <p>A <code>rewriteSystem</code> is a very powerful instruction, it says that |
| 2331 | any URI starting with a given prefix should be looked at another URI |
| 2332 | constructed by replacing the prefix with an new one. In effect this acts like |
| 2333 | a cache system for a full area of the Web. In practice it is extremely useful |
| 2334 | with a file prefix if you have installed a copy of those resources on your |
| 2335 | local system.</p> |
| 2336 | <pre>... |
| 2337 | <delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //" |
| 2338 | catalog="file:///usr/share/xml/docbook.xml"/> |
| 2339 | <delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML" |
| 2340 | catalog="file:///usr/share/xml/docbook.xml"/> |
| 2341 | <delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML" |
| 2342 | catalog="file:///usr/share/xml/docbook.xml"/> |
| 2343 | <delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/" |
| 2344 | catalog="file:///usr/share/xml/docbook.xml"/> |
| 2345 | <delegateURI uriStartString="http://www.oasis-open.org/docbook/" |
| 2346 | catalog="file:///usr/share/xml/docbook.xml"/> |
| 2347 | ...</pre> |
| 2348 | |
| 2349 | <p>Delegation is the core features which allows to build a tree of catalogs, |
| 2350 | easier to maintain than a single catalog, based on Public Identifier, System |
| 2351 | Identifier or URI prefixes it instructs the catalog software to look up |
| 2352 | entries in another resource. This feature allow to build hierarchies of |
| 2353 | catalogs, the set of entries presented should be sufficient to redirect the |
| 2354 | resolution of all DocBook references to the specific catalog in |
| 2355 | <code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all |
| 2356 | references for DocBook 4.2.1 to a specific catalog installed at the same time |
| 2357 | as the DocBook resources on the local machine.</p> |
| 2358 | |
| 2359 | <h3><a name="reference">How to tune catalog usage:</a></h3> |
| 2360 | |
| 2361 | <p>The user can change the default catalog behaviour by redirecting queries |
| 2362 | to its own set of catalogs, this can be done by setting the |
| 2363 | <code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an |
| 2364 | empty one should deactivate loading the default <code>/etc/xml/catalog</code> |
| 2365 | default catalog</p> |
| 2366 | |
| 2367 | <h3><a name="validate">How to debug catalog processing:</a></h3> |
| 2368 | |
| 2369 | <p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will |
| 2370 | make libxml output debugging informations for each catalog operations, for |
| 2371 | example:</p> |
| 2372 | <pre>orchis:~/XML -> xmllint --memory --noout test/ent2 |
| 2373 | warning: failed to load external entity "title.xml" |
| 2374 | orchis:~/XML -> export XML_DEBUG_CATALOG= |
| 2375 | orchis:~/XML -> xmllint --memory --noout test/ent2 |
| 2376 | Failed to parse catalog /etc/xml/catalog |
| 2377 | Failed to parse catalog /etc/xml/catalog |
| 2378 | warning: failed to load external entity "title.xml" |
| 2379 | Catalogs cleanup |
| 2380 | orchis:~/XML -> </pre> |
| 2381 | |
| 2382 | <p>The test/ent2 references an entity, running the parser from memory makes |
| 2383 | the base URI unavailable and the the "title.xml" entity cannot be loaded. |
| 2384 | Setting up the debug environment variable allows to detect that an attempt is |
| 2385 | made to load the <code>/etc/xml/catalog</code> but since it's not present the |
| 2386 | resolution fails.</p> |
| 2387 | |
| 2388 | <p>But the most advanced way to debug XML catalog processing is to use the |
| 2389 | <strong>xmlcatalog</strong> command shipped with libxml2, it allows to load |
| 2390 | catalogs and make resolution queries to see what is going on. This is also |
| 2391 | used for the regression tests:</p> |
| 2392 | <pre>orchis:~/XML -> ./xmlcatalog test/catalogs/docbook.xml \ |
| 2393 | "-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2394 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd |
| 2395 | orchis:~/XML -> </pre> |
| 2396 | |
| 2397 | <p>For debugging what is going on, adding one -v flags increase the verbosity |
| 2398 | level to indicate the processing done (adding a second flag also indicate |
| 2399 | what elements are recognized at parsing):</p> |
| 2400 | <pre>orchis:~/XML -> ./xmlcatalog -v test/catalogs/docbook.xml \ |
| 2401 | "-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2402 | Parsing catalog test/catalogs/docbook.xml's content |
| 2403 | Found public match -//OASIS//DTD DocBook XML V4.1.2//EN |
| 2404 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd |
| 2405 | Catalogs cleanup |
| 2406 | orchis:~/XML -> </pre> |
| 2407 | |
| 2408 | <p>A shell interface is also available to debug and process multiple queries |
| 2409 | (and for regression tests):</p> |
| 2410 | <pre>orchis:~/XML -> ./xmlcatalog -shell test/catalogs/docbook.xml \ |
| 2411 | "-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2412 | > help |
| 2413 | Commands available: |
| 2414 | public PublicID: make a PUBLIC identifier lookup |
| 2415 | system SystemID: make a SYSTEM identifier lookup |
| 2416 | resolve PublicID SystemID: do a full resolver lookup |
| 2417 | add 'type' 'orig' 'replace' : add an entry |
| 2418 | del 'values' : remove values |
| 2419 | dump: print the current catalog state |
| 2420 | debug: increase the verbosity level |
| 2421 | quiet: decrease the verbosity level |
| 2422 | exit: quit the shell |
| 2423 | > public "-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2424 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd |
| 2425 | > quit |
| 2426 | orchis:~/XML -> </pre> |
| 2427 | |
| 2428 | <p>This should be sufficient for most debugging purpose, this was actually |
| 2429 | used heavily to debug the XML Catalog implementation itself.</p> |
| 2430 | |
| 2431 | <h3><a name="Declaring">How to create and maintain</a> catalogs:</h3> |
| 2432 | |
| 2433 | <p>Basically XML Catalogs are XML files, you can either use XML tools to |
| 2434 | manage them or use <strong>xmlcatalog</strong> for this. The basic step is |
| 2435 | to create a catalog the -create option provide this facility:</p> |
| 2436 | <pre>orchis:~/XML -> ./xmlcatalog --create tst.xml |
| 2437 | <?xml version="1.0"?> |
| 2438 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" |
| 2439 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> |
| 2440 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/> |
| 2441 | orchis:~/XML -> </pre> |
| 2442 | |
| 2443 | <p>By default xmlcatalog does not overwrite the original catalog and save the |
| 2444 | result on the standard output, this can be overridden using the -noout |
| 2445 | option. The <code>-add</code> command allows to add entries in the |
| 2446 | catalog:</p> |
| 2447 | <pre>orchis:~/XML -> ./xmlcatalog --noout --create --add "public" \ |
| 2448 | "-//OASIS//DTD DocBook XML V4.1.2//EN" \ |
| 2449 | http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml |
| 2450 | orchis:~/XML -> cat tst.xml |
| 2451 | <?xml version="1.0"?> |
| 2452 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \ |
| 2453 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> |
| 2454 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"> |
| 2455 | <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN" |
| 2456 | uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/> |
| 2457 | </catalog> |
| 2458 | orchis:~/XML -> </pre> |
| 2459 | |
| 2460 | <p>The <code>-add</code> option will always take 3 parameters even if some of |
| 2461 | the XML Catalog constructs (like nextCatalog) will have only a single |
| 2462 | argument, just pass a third empty string, it will be ignored.</p> |
| 2463 | |
| 2464 | <p>Similarly the <code>-del</code> option remove matching entries from the |
| 2465 | catalog:</p> |
| 2466 | <pre>orchis:~/XML -> ./xmlcatalog --del \ |
| 2467 | "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml |
| 2468 | <?xml version="1.0"?> |
| 2469 | <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" |
| 2470 | "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd"> |
| 2471 | <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/> |
| 2472 | orchis:~/XML -> </pre> |
| 2473 | |
| 2474 | <p>The catalog is now empty. Note that the matching of <code>-del</code> is |
| 2475 | exact and would have worked in a similar fashion with the Public ID |
| 2476 | string.</p> |
| 2477 | |
| 2478 | <p>This is rudimentary but should be sufficient to manage a not too complex |
| 2479 | catalog tree of resources.</p> |
| 2480 | |
| 2481 | <h3><a name="implemento">The implementor corner quick review of the |
| 2482 | API:</a></h3> |
| 2483 | |
| 2484 | <p>First, and like for every other module of libxml, there is an |
| 2485 | automatically generated <a href="html/libxml-catalog.html">API page for |
| 2486 | catalog support</a>.</p> |
| 2487 | |
| 2488 | <p>The header for the catalog interfaces should be included as:</p> |
| 2489 | <pre>#include <libxml/catalog.h></pre> |
| 2490 | |
| 2491 | <p>The API is voluntarily kept very simple. First it is not obvious that |
| 2492 | applications really need access to it since it is the default behaviour of |
| 2493 | libxml (Note: it is possible to completely override libxml default catalog by |
| 2494 | using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to |
| 2495 | plug an application specific resolver).</p> |
| 2496 | |
| 2497 | <p>Basically libxml support 2 catalog lists:</p> |
| 2498 | <ul> |
| 2499 | <li>the default one, global shared by all the application</li> |
| 2500 | <li>a per-document catalog, this one is built if the document uses the |
| 2501 | <code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is |
| 2502 | associated to the parser context and destroyed when the parsing context |
| 2503 | is destroyed.</li> |
| 2504 | </ul> |
| 2505 | |
| 2506 | <p>the document one will be used first if it exists.</p> |
| 2507 | |
| 2508 | <h4>Initialization routines:</h4> |
| 2509 | |
| 2510 | <p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be |
| 2511 | used at startup to initialize the catalog, if the catalog should be |
| 2512 | initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs() |
| 2513 | should be called before xmlInitializeCatalog() which would otherwise do a |
| 2514 | default initialization first.</p> |
| 2515 | |
| 2516 | <p>The xmlCatalogAddLocal() call is used by the parser to grow the document |
| 2517 | own catalog list if needed.</p> |
| 2518 | |
| 2519 | <h4>Preferences setup:</h4> |
| 2520 | |
| 2521 | <p>The XML Catalog spec requires the possibility to select default |
| 2522 | preferences between public and system delegation, |
| 2523 | xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and |
| 2524 | xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should |
| 2525 | be forbidden, allowed for global catalog, for document catalog or both, the |
| 2526 | default is to allow both.</p> |
| 2527 | |
| 2528 | <p>And of course xmlCatalogSetDebug() allows to generate debug messages |
| 2529 | (through the xmlGenericError() mechanism).</p> |
| 2530 | |
| 2531 | <h4>Querying routines:</h4> |
| 2532 | |
| 2533 | <p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic() |
| 2534 | and xmlCatalogResolveURI() are relatively explicit if you read the XML |
| 2535 | Catalog specification they correspond to section 7 algorithms, they should |
| 2536 | also work if you have loaded an SGML catalog with a simplified semantic.</p> |
| 2537 | |
| 2538 | <p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but |
| 2539 | operate on the document catalog list</p> |
| 2540 | |
| 2541 | <h4>Cleanup and Miscellaneous:</h4> |
| 2542 | |
| 2543 | <p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is |
| 2544 | the per-document equivalent.</p> |
| 2545 | |
| 2546 | <p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the |
| 2547 | first catalog in the global list, and xmlCatalogDump() allows to dump a |
| 2548 | catalog state, those routines are primarily designed for xmlcatalog, I'm not |
| 2549 | sure that exposing more complex interfaces (like navigation ones) would be |
| 2550 | really useful.</p> |
| 2551 | |
| 2552 | <p>The xmlParseCatalogFile() is a function used to load XML Catalog files, |
| 2553 | it's similar as xmlParseFile() except it bypass all catalog lookups, it's |
| 2554 | provided because this functionality may be useful for client tools.</p> |
| 2555 | |
| 2556 | <h4>threaded environments:</h4> |
| 2557 | |
| 2558 | <p>Since the catalog tree is built progressively, some care has been taken to |
| 2559 | try to avoid troubles in multithreaded environments. The code is now thread |
| 2560 | safe assuming that the libxml library has been compiled with threads |
| 2561 | support.</p> |
| 2562 | |
| 2563 | <p></p> |
| 2564 | |
| 2565 | <h3><a name="Other">Other resources</a></h3> |
| 2566 | |
| 2567 | <p>The XML Catalog specification is relatively recent so there isn't much |
| 2568 | literature to point at:</p> |
| 2569 | <ul> |
| 2570 | <li>You can find an good rant from Norm Walsh about <a |
| 2571 | href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the |
| 2572 | need for catalogs</a>, it provides a lot of context informations even if |
| 2573 | I don't agree with everything presented.</li> |
| 2574 | <li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML |
| 2575 | catalog proposal</a> from John Cowan</li> |
| 2576 | <li>The <a href="http://www.rddl.org/">Resource Directory Description |
| 2577 | Language</a> (RDDL) another catalog system but more oriented toward |
| 2578 | providing metadata for XML namespaces.</li> |
| 2579 | <li>the page from the OASIS Technical <a |
| 2580 | href="http://www.oasis-open.org/committees/entity/">Committee on Entity |
| 2581 | Resolution</a> who maintains XML Catalog, you will find pointers to the |
| 2582 | specification update, some background and pointers to others tools |
| 2583 | providing XML Catalog support</li> |
| 2584 | <li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a |
| 2585 | mall tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems to |
| 2586 | work fine for me</li> |
| 2587 | <li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog |
| 2588 | manual page</a></li> |
| 2589 | </ul> |
| 2590 | |
| 2591 | <p>If you have suggestions for corrections or additions, simply contact |
| 2592 | me:</p> |
| 2593 | |
| 2594 | <h2><a name="library">The parser interfaces</a></h2> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2595 | |
| 2596 | <p>This section is directly intended to help programmers getting bootstrapped |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2597 | using the XML library from the C language. It is not intended to be |
| 2598 | extensive. I hope the automatically generated documents will provide the |
| 2599 | completeness required, but as a separate set of documents. The interfaces of |
| 2600 | the XML library are by principle low level, there is nearly zero abstraction. |
| 2601 | Those interested in a higher level API should <a href="#DOM">look at |
| 2602 | DOM</a>.</p> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 2603 | |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 2604 | <p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are |
| 2605 | separated from the <a href="html/libxml-htmlparser.html">HTML parser |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2606 | interfaces</a>. Let's have a look at how the XML parser can be called:</p> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2607 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2608 | <h3><a name="Invoking">Invoking the parser : the pull method</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2609 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2610 | <p>Usually, the first thing to do is to read an XML input. The parser accepts |
| 2611 | documents either from in-memory strings or from files. The functions are |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2612 | defined in "parser.h":</p> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2613 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2614 | <dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2615 | <dd><p>Parse a null-terminated string containing the document.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2616 | </dd> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2617 | </dl> |
| 2618 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2619 | <dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2620 | <dd><p>Parse an XML document contained in a (possibly compressed) |
| 2621 | file.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2622 | </dd> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2623 | </dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2624 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2625 | <p>The parser returns a pointer to the document structure (or NULL in case of |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2626 | failure).</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2627 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2628 | <h3 id="Invoking1">Invoking the parser: the push method</h3> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2629 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2630 | <p>In order for the application to keep the control when the document is |
| 2631 | being fetched (which is common for GUI based programs) libxml provides a push |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2632 | interface, too, as of version 1.8.3. Here are the interface functions:</p> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2633 | <pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax, |
| 2634 | void *user_data, |
| 2635 | const char *chunk, |
| 2636 | int size, |
| 2637 | const char *filename); |
| 2638 | int xmlParseChunk (xmlParserCtxtPtr ctxt, |
| 2639 | const char *chunk, |
| 2640 | int size, |
| 2641 | int terminate);</pre> |
| 2642 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2643 | <p>and here is a simple example showing how to use the interface:</p> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2644 | <pre> FILE *f; |
| 2645 | |
| 2646 | f = fopen(filename, "r"); |
| 2647 | if (f != NULL) { |
| 2648 | int res, size = 1024; |
| 2649 | char chars[1024]; |
| 2650 | xmlParserCtxtPtr ctxt; |
| 2651 | |
| 2652 | res = fread(chars, 1, 4, f); |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2653 | if (res > 0) { |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2654 | ctxt = xmlCreatePushParserCtxt(NULL, NULL, |
| 2655 | chars, res, filename); |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2656 | while ((res = fread(chars, 1, size, f)) > 0) { |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2657 | xmlParseChunk(ctxt, chars, res, 0); |
| 2658 | } |
| 2659 | xmlParseChunk(ctxt, chars, 0, 1); |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2660 | doc = ctxt->myDoc; |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2661 | xmlFreeParserCtxt(ctxt); |
| 2662 | } |
| 2663 | }</pre> |
| 2664 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 2665 | <p>The HTML parser embedded into libxml also has a push interface; the |
| 2666 | functions are just prefixed by "html" rather than "xml".</p> |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2667 | |
| 2668 | <h3 id="Invoking2">Invoking the parser: the SAX interface</h3> |
| 2669 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 2670 | <p>The tree-building interface makes the parser memory-hungry, first loading |
| 2671 | the document in memory and then building the tree itself. Reading a document |
| 2672 | without building the tree is possible using the SAX interfaces (see SAX.h and |
| 2673 | <a href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">James |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2674 | Henstridge's documentation</a>). Note also that the push interface can be |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2675 | limited to SAX: just use the two first arguments of |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2676 | <code>xmlCreatePushParserCtxt()</code>.</p> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 2677 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2678 | <h3><a name="Building">Building a tree from scratch</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2679 | |
| 2680 | <p>The other way to get an XML tree in memory is by building it. Basically |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2681 | there is a set of functions dedicated to building new elements. (These are |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2682 | also described in <libxml/tree.h>.) For example, here is a piece of |
| 2683 | code that produces the XML document used in the previous examples:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2684 | <pre> #include <libxml/tree.h> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 2685 | xmlDocPtr doc; |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2686 | xmlNodePtr tree, subtree; |
| 2687 | |
| 2688 | doc = xmlNewDoc("1.0"); |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2689 | doc->children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL); |
| 2690 | xmlSetProp(doc->children, "prop1", "gnome is great"); |
| 2691 | xmlSetProp(doc->children, "prop2", "& linux too"); |
| 2692 | tree = xmlNewChild(doc->children, NULL, "head", NULL); |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2693 | subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome"); |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2694 | tree = xmlNewChild(doc->children, NULL, "chapter", NULL); |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2695 | subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure"); |
| 2696 | subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ..."); |
| 2697 | subtree = xmlNewChild(tree, NULL, "image", NULL); |
| 2698 | xmlSetProp(subtree, "href", "linus.gif");</pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2699 | |
| 2700 | <p>Not really rocket science ...</p> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2701 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2702 | <h3><a name="Traversing">Traversing the tree</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2703 | |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 2704 | <p>Basically by <a href="html/libxml-tree.html">including "tree.h"</a> your |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2705 | code has access to the internal structure of all the elements of the tree. |
| 2706 | The names should be somewhat simple like <strong>parent</strong>, |
Daniel Veillard | 306be99 | 2000-07-03 12:38:45 +0000 | [diff] [blame] | 2707 | <strong>children</strong>, <strong>next</strong>, <strong>prev</strong>, |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2708 | <strong>properties</strong>, etc... For example, still with the previous |
Daniel Veillard | 0142b84 | 2000-01-14 14:45:24 +0000 | [diff] [blame] | 2709 | example:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2710 | <pre><code>doc->children->children->children</code></pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2711 | |
| 2712 | <p>points to the title element,</p> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2713 | <pre>doc->children->children->next->children->children</pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2714 | |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2715 | <p>points to the text node containing the chapter title "The Linux |
| 2716 | adventure".</p> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2717 | |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 2718 | <p><strong>NOTE</strong>: XML allows <em>PI</em>s and <em>comments</em> to be |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2719 | present before the document root, so <code>doc->children</code> may point |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2720 | to an element which is not the document Root Element; a function |
Daniel Veillard | 5cb5ab8 | 1999-12-21 15:35:29 +0000 | [diff] [blame] | 2721 | <code>xmlDocGetRootElement()</code> was added for this purpose.</p> |
Daniel Veillard | b24054a | 1999-12-18 15:32:46 +0000 | [diff] [blame] | 2722 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2723 | <h3><a name="Modifying">Modifying the tree</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2724 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2725 | <p>Functions are provided for reading and writing the document content. Here |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 2726 | is an excerpt from the <a href="html/libxml-tree.html">tree API</a>:</p> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2727 | <dl> |
Daniel Veillard | dd6b367 | 1999-09-23 22:19:22 +0000 | [diff] [blame] | 2728 | <dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const |
| 2729 | xmlChar *value);</code></dt> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2730 | <dd><p>This sets (or changes) an attribute carried by an ELEMENT node. |
| 2731 | The value can be NULL.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2732 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2733 | </dl> |
| 2734 | <dl> |
Daniel Veillard | dd6b367 | 1999-09-23 22:19:22 +0000 | [diff] [blame] | 2735 | <dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2736 | *name);</code></dt> |
Daniel Veillard | c92c304 | 2000-09-29 02:42:04 +0000 | [diff] [blame] | 2737 | <dd><p>This function returns a pointer to new copy of the property |
| 2738 | content. Note that the user must deallocate the result.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2739 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2740 | </dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2741 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2742 | <p>Two functions are provided for reading and writing the text associated |
| 2743 | with elements:</p> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2744 | <dl> |
Daniel Veillard | dd6b367 | 1999-09-23 22:19:22 +0000 | [diff] [blame] | 2745 | <dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2746 | *value);</code></dt> |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 2747 | <dd><p>This function takes an "external" string and converts it to one |
| 2748 | text node or possibly to a list of entity and text nodes. All |
| 2749 | non-predefined entity references like &Gnome; will be stored |
| 2750 | internally as entity nodes, hence the result of the function may not be |
| 2751 | a single node.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2752 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2753 | </dl> |
| 2754 | <dl> |
Daniel Veillard | dd6b367 | 1999-09-23 22:19:22 +0000 | [diff] [blame] | 2755 | <dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2756 | inLine);</code></dt> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2757 | <dd><p>This function is the inverse of |
| 2758 | <code>xmlStringGetNodeList()</code>. It generates a new string |
| 2759 | containing the content of the text and entity nodes. Note the extra |
| 2760 | argument inLine. If this argument is set to 1, the function will expand |
| 2761 | entity references. For example, instead of returning the &Gnome; |
| 2762 | XML encoding in the string, it will substitute it with its value (say, |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2763 | "GNU Network Object Model Environment").</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2764 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2765 | </dl> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2766 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2767 | <h3><a name="Saving">Saving a tree</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2768 | |
| 2769 | <p>Basically 3 options are possible:</p> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2770 | <dl> |
Daniel Veillard | dd6b367 | 1999-09-23 22:19:22 +0000 | [diff] [blame] | 2771 | <dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2772 | *size);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2773 | <dd><p>Returns a buffer into which the document has been saved.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2774 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2775 | </dl> |
| 2776 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2777 | <dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2778 | <dd><p>Dumps a document to an open file descriptor.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2779 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2780 | </dl> |
| 2781 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2782 | <dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt> |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2783 | <dd><p>Saves the document to a file. In this case, the compression |
| 2784 | interface is triggered if it has been turned on.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2785 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2786 | </dl> |
Daniel Veillard | 10c6a8f | 1998-10-28 01:00:12 +0000 | [diff] [blame] | 2787 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2788 | <h3><a name="Compressio">Compression</a></h3> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2789 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2790 | <p>The library transparently handles compression when doing file-based |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2791 | accesses. The level of compression on saves can be turned on either globally |
| 2792 | or individually for one file:</p> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2793 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2794 | <dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2795 | <dd><p>Gets the document compression ratio (0-9).</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2796 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2797 | </dl> |
| 2798 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2799 | <dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2800 | <dd><p>Sets the document compression ratio.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2801 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2802 | </dl> |
| 2803 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2804 | <dt><code>int xmlGetCompressMode(void);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2805 | <dd><p>Gets the default compression ratio.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2806 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2807 | </dl> |
| 2808 | <dl> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2809 | <dt><code>void xmlSetCompressMode(int mode);</code></dt> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2810 | <dd><p>Sets the default compression ratio.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 2811 | </dd> |
Daniel Veillard | 25940b7 | 1998-10-29 05:51:30 +0000 | [diff] [blame] | 2812 | </dl> |
| 2813 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2814 | <h2><a name="Entities">Entities or no entities</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2815 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2816 | <p>Entities in principle are similar to simple C macros. An entity defines an |
| 2817 | abbreviation for a given string that you can reuse many times throughout the |
| 2818 | content of your document. Entities are especially useful when a given string |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2819 | may occur frequently within a document, or to confine the change needed to a |
| 2820 | document to a restricted area in the internal subset of the document (at the |
| 2821 | beginning). Example:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2822 | <pre>1 <?xml version="1.0"?> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2823 | 2 <!DOCTYPE EXAMPLE SYSTEM "example.dtd" [ |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2824 | 3 <!ENTITY xml "Extensible Markup Language"> |
| 2825 | 4 ]> |
| 2826 | 5 <EXAMPLE> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2827 | 6 &xml; |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2828 | 7 </EXAMPLE></pre> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2829 | |
| 2830 | <p>Line 3 declares the xml entity. Line 6 uses the xml entity, by prefixing |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2831 | its name with '&' and following it by ';' without any spaces added. There |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2832 | are 5 predefined entities in libxml allowing you to escape charaters with |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2833 | predefined meaning in some parts of the xml document content: |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2834 | <strong>&lt;</strong> for the character '<', <strong>&gt;</strong> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2835 | for the character '>', <strong>&apos;</strong> for the character ''', |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2836 | <strong>&quot;</strong> for the character '"', and |
| 2837 | <strong>&amp;</strong> for the character '&'.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2838 | |
| 2839 | <p>One of the problems related to entities is that you may want the parser to |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2840 | substitute an entity's content so that you can see the replacement text in |
| 2841 | your application. Or you may prefer to keep entity references as such in the |
| 2842 | content to be able to save the document back without losing this usually |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2843 | precious information (if the user went through the pain of explicitly |
| 2844 | defining entities, he may have a a rather negative attitude if you blindly |
| 2845 | susbtitute them as saving time). The <a |
Daniel Veillard | 9cb5ff4 | 2001-01-29 08:22:21 +0000 | [diff] [blame] | 2846 | href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a> |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2847 | function allows you to check and change the behaviour, which is to not |
| 2848 | substitute entities by default.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2849 | |
| 2850 | <p>Here is the DOM tree built by libxml for the previous document in the |
| 2851 | default case:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2852 | <pre>/gnome/src/gnome-xml -> ./xmllint --debug test/ent1 |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2853 | DOCUMENT |
| 2854 | version=1.0 |
| 2855 | ELEMENT EXAMPLE |
| 2856 | TEXT |
| 2857 | content= |
| 2858 | ENTITY_REF |
| 2859 | INTERNAL_GENERAL_ENTITY xml |
| 2860 | content=Extensible Markup Language |
| 2861 | TEXT |
| 2862 | content=</pre> |
| 2863 | |
| 2864 | <p>And here is the result when substituting entities:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2865 | <pre>/gnome/src/gnome-xml -> ./tester --debug --noent test/ent1 |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2866 | DOCUMENT |
| 2867 | version=1.0 |
| 2868 | ELEMENT EXAMPLE |
| 2869 | TEXT |
| 2870 | content= Extensible Markup Language</pre> |
| 2871 | |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2872 | <p>So, entities or no entities? Basically, it depends on your use case. I |
| 2873 | suggest that you keep the non-substituting default behaviour and avoid using |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2874 | entities in your XML document or data if you are not willing to handle the |
| 2875 | entity references elements in the DOM tree.</p> |
| 2876 | |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2877 | <p>Note that at save time libxml enforces the conversion of the predefined |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2878 | entities where necessary to prevent well-formedness problems, and will also |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2879 | transparently replace those with chars (i.e. it will not generate entity |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2880 | reference elements in the DOM tree or call the reference() SAX callback when |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2881 | finding them in the input).</p> |
| 2882 | |
Daniel Veillard | 7b9c4b7 | 2000-08-25 16:26:50 +0000 | [diff] [blame] | 2883 | <p><span style="background-color: #FF0000">WARNING</span>: handling entities |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2884 | on top of the libxml SAX interface is difficult!!! If you plan to use |
Daniel Veillard | 7b9c4b7 | 2000-08-25 16:26:50 +0000 | [diff] [blame] | 2885 | non-predefined entities in your documents, then the learning cuvre to handle |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2886 | then using the SAX API may be long. If you plan to use complex documents, I |
Daniel Veillard | 7b9c4b7 | 2000-08-25 16:26:50 +0000 | [diff] [blame] | 2887 | strongly suggest you consider using the DOM interface instead and let libxml |
Daniel Veillard | 8c6d6af | 2000-08-25 17:14:13 +0000 | [diff] [blame] | 2888 | deal with the complexity rather than trying to do it yourself.</p> |
Daniel Veillard | 7b9c4b7 | 2000-08-25 16:26:50 +0000 | [diff] [blame] | 2889 | |
Daniel Veillard | 2f4dfc4 | 1999-09-24 14:03:48 +0000 | [diff] [blame] | 2890 | <h2><a name="Namespaces">Namespaces</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2891 | |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 2892 | <p>The libxml library implements <a |
| 2893 | href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by |
| 2894 | recognizing namespace contructs in the input, and does namespace lookup |
| 2895 | automatically when building the DOM tree. A namespace declaration is |
| 2896 | associated with an in-memory structure and all elements or attributes within |
| 2897 | that namespace point to it. Hence testing the namespace is a simple and fast |
| 2898 | equality operation at the user level.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2899 | |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2900 | <p>I suggest that people using libxml use a namespace, and declare it in the |
| 2901 | root element of their document as the default namespace. Then they don't need |
| 2902 | to use the prefix in the content but we will have a basis for future semantic |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2903 | refinement and merging of data from different sources. This doesn't increase |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 2904 | the size of the XML output significantly, but significantly increases its |
| 2905 | value in the long-term. Example:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2906 | <pre><mydoc xmlns="http://mydoc.example.org/schemas/"> |
| 2907 | <elem1>...</elem1> |
| 2908 | <elem2>...</elem2> |
| 2909 | </mydoc></pre> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2910 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 2911 | <p>The namespace value has to be an absolute URL, but the URL doesn't have to |
| 2912 | point to any existing resource on the Web. It will bind all the element and |
| 2913 | atributes with that URL. I suggest to use an URL within a domain you control, |
| 2914 | and that the URL should contain some kind of version information if possible. |
| 2915 | For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a good |
| 2916 | namespace scheme.</p> |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 2917 | |
| 2918 | <p>Then when you load a file, make sure that a namespace carrying the |
Daniel Veillard | 88f00ae | 2000-03-02 00:15:55 +0000 | [diff] [blame] | 2919 | version-independent prefix is installed on the root element of your document, |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2920 | and if the version information don't match something you know, warn the user |
| 2921 | and be liberal in what you accept as the input. Also do *not* try to base |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2922 | namespace checking on the prefix value. <foo:text> may be exactly the |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2923 | same as <bar:text> in another document. What really matters is the URI |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 2924 | associated with the element or the attribute, not the prefix string (which is |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2925 | just a shortcut for the full URI). In libxml, element and attributes have an |
Daniel Veillard | ec30341 | 2000-03-24 13:41:54 +0000 | [diff] [blame] | 2926 | <code>ns</code> field pointing to an xmlNs structure detailing the namespace |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2927 | prefix and its URI.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2928 | |
| 2929 | <p>@@Interfaces@@</p> |
| 2930 | |
| 2931 | <p>@@Examples@@</p> |
| 2932 | |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2933 | <p>Usually people object to using namespaces together with validity checking. |
| 2934 | I will try to make sure that using namespaces won't break validity checking, |
| 2935 | so even if you plan to use or currently are using validation I strongly |
Daniel Veillard | f13e1ed | 2000-03-06 07:41:49 +0000 | [diff] [blame] | 2936 | suggest adding namespaces to your document. A default namespace scheme |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2937 | <code>xmlns="http://...."</code> should not break validity even on less |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 2938 | flexible parsers. Using namespaces to mix and differentiate content coming |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 2939 | from multiple DTDs will certainly break current validation schemes. I will |
| 2940 | try to provide ways to do this, but this may not be portable or |
| 2941 | standardized.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2942 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2943 | <h2><a name="Upgrading">Upgrading 1.x code</a></h2> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2944 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2945 | <p>Incompatible changes:</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2946 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2947 | <p>Version 2 of libxml is the first version introducing serious backward |
| 2948 | incompatible changes. The main goals were:</p> |
| 2949 | <ul> |
| 2950 | <li>a general cleanup. A number of mistakes inherited from the very early |
| 2951 | versions couldn't be changed due to compatibility constraints. Example |
| 2952 | the "childs" element in the nodes.</li> |
| 2953 | <li>Uniformization of the various nodes, at least for their header and link |
| 2954 | parts (doc, parent, children, prev, next), the goal is a simpler |
| 2955 | programming model and simplifying the task of the DOM implementors.</li> |
| 2956 | <li>better conformances to the XML specification, for example version 1.x |
| 2957 | had an heuristic to try to detect ignorable white spaces. As a result the |
| 2958 | SAX event generated were ignorableWhitespace() while the spec requires |
| 2959 | character() in that case. This also mean that a number of DOM node |
| 2960 | containing blank text may populate the DOM tree which were not present |
| 2961 | before.</li> |
| 2962 | </ul> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2963 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2964 | <h3>How to fix libxml-1.x code:</h3> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 2965 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 2966 | <p>So client code of libxml designed to run with version 1.x may have to be |
| 2967 | changed to compile against version 2.x of libxml. Here is a list of changes |
| 2968 | that I have collected, they may not be sufficient, so in case you find other |
| 2969 | change which are required, <a href="mailto:Daniel.Ïeillardw3.org">drop me a |
| 2970 | mail</a>:</p> |
| 2971 | <ol> |
| 2972 | <li>The package name have changed from libxml to libxml2, the library name |
| 2973 | is now -lxml2 . There is a new xml2-config script which should be used to |
| 2974 | select the right parameters libxml2</li> |
| 2975 | <li>Node <strong>childs</strong> field has been renamed |
| 2976 | <strong>children</strong> so s/childs/children/g should be applied |
| 2977 | (probablility of having "childs" anywere else is close to 0+</li> |
| 2978 | <li>The document don't have anymore a <strong>root</strong> element it has |
| 2979 | been replaced by <strong>children</strong> and usually you will get a |
| 2980 | list of element here. For example a Dtd element for the internal subset |
| 2981 | and it's declaration may be found in that list, as well as processing |
| 2982 | instructions or comments found before or after the document root element. |
| 2983 | Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of |
| 2984 | a document. Alternatively if you are sure to not reference Dtds nor have |
| 2985 | PIs or comments before or after the root element |
| 2986 | s/->root/->children/g will probably do it.</li> |
| 2987 | <li>The white space issue, this one is more complex, unless special case of |
| 2988 | validating parsing, the line breaks and spaces usually used for indenting |
| 2989 | and formatting the document content becomes significant. So they are |
| 2990 | reported by SAX and if your using the DOM tree, corresponding nodes are |
| 2991 | generated. Too approach can be taken: |
| 2992 | <ol> |
| 2993 | <li>lazy one, use the compatibility call |
| 2994 | <strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are |
| 2995 | relying on a special (and possibly broken) set of heuristics of |
| 2996 | libxml to detect ignorable blanks. Don't complain if it breaks or |
| 2997 | make your application not 100% clean w.r.t. to it's input.</li> |
| 2998 | <li>the Right Way: change you code to accept possibly unsignificant |
| 2999 | blanks characters, or have your tree populated with weird blank text |
| 3000 | nodes. You can spot them using the comodity function |
| 3001 | <strong>xmlIsBlankNode(node)</strong> returning 1 for such blank |
| 3002 | nodes.</li> |
| 3003 | </ol> |
| 3004 | <p>Note also that with the new default the output functions don't add any |
| 3005 | extra indentation when saving a tree in order to be able to round trip |
| 3006 | (read and save) without inflating the document with extra formatting |
| 3007 | chars.</p> |
| 3008 | </li> |
| 3009 | <li>The include path has changed to $prefix/libxml/ and the includes |
| 3010 | themselves uses this new prefix in includes instructions... If you are |
| 3011 | using (as expected) the |
| 3012 | <pre>xml2-config --cflags</pre> |
| 3013 | <p>output to generate you compile commands this will probably work out of |
| 3014 | the box</p> |
| 3015 | </li> |
| 3016 | <li>xmlDetectCharEncoding takes an extra argument indicating the lenght in |
| 3017 | byte of the head of the document available for character detection.</li> |
| 3018 | </ol> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3019 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3020 | <h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3021 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3022 | <p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released |
| 3023 | to allow smoth upgrade of existing libxml v1code while retaining |
| 3024 | compatibility. They offers the following:</p> |
| 3025 | <ol> |
| 3026 | <li>similar include naming, one should use |
| 3027 | <strong>#include<libxml/...></strong> in both cases.</li> |
| 3028 | <li>similar identifiers defined via macros for the child and root fields: |
| 3029 | respectively <strong>xmlChildrenNode</strong> and |
| 3030 | <strong>xmlRootNode</strong></li> |
| 3031 | <li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be |
| 3032 | inserted once in the client code</li> |
| 3033 | </ol> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3034 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3035 | <p>So the roadmap to upgrade your existing libxml applications is the |
| 3036 | following:</p> |
| 3037 | <ol> |
| 3038 | <li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li> |
| 3039 | <li>find all occurences where the xmlDoc <strong>root</strong> field is |
| 3040 | used and change it to <strong>xmlRootNode</strong></li> |
| 3041 | <li>similary find all occurences where the xmlNode <strong>childs</strong> |
| 3042 | field is used and change it to <strong>xmlChildrenNode</strong></li> |
| 3043 | <li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your |
| 3044 | <strong>main()</strong> or in the library init entry point</li> |
| 3045 | <li>Recompile, check compatibility, it should still work</li> |
| 3046 | <li>Change your configure script to look first for xml2-config and fallback |
| 3047 | using xml-config . Use the --cflags and --libs ouptut of the command as |
| 3048 | the Include and Linking parameters needed to use libxml.</li> |
| 3049 | <li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and |
| 3050 | libxml-devel-1.8.y can be kept simultaneously)</li> |
| 3051 | <li>remove your config.cache, relaunch your configuration mechanism, and |
| 3052 | recompile, if steps 2 and 3 were done right it should compile as-is</li> |
| 3053 | <li>Test that your application is still running correctly, if not this may |
| 3054 | be due to extra empty nodes due to formating spaces being kept in libxml2 |
| 3055 | contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your |
| 3056 | code before calling the parser (next to |
| 3057 | <strong>LIBXML_TEST_VERSION</strong> is a fine place).</li> |
| 3058 | </ol> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3059 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3060 | <p>Following those steps should work. It worked for some of my own code.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3061 | |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3062 | <p>Let me put some emphasis on the fact that there is far more changes from |
| 3063 | libxml 1.x to 2.x than the ones you may have to patch for. The overall code |
| 3064 | has been considerably cleaned up and the conformance to the XML specification |
| 3065 | has been drastically improved too. Don't take those changes as an excuse to |
| 3066 | not upgrade, it may cost a lot on the long term ...</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3067 | |
Daniel Veillard | 52dcab3 | 2001-10-30 12:51:17 +0000 | [diff] [blame] | 3068 | <h2><a name="Thread">Thread safety</a></h2> |
| 3069 | |
| 3070 | <p>Starting with 2.4.7, libxml makes provisions to ensure that concurent |
| 3071 | threads can safely work in parallel parsing different documents. There is |
| 3072 | however a couple of things to do to ensure it:</p> |
| 3073 | <ul> |
| 3074 | <li>configure the library accordingly using the --with-threads options</li> |
| 3075 | <li>call xmlInitParser() in the "main" thread before using any of the |
| 3076 | libxml API (except possibly selecting a different memory allocator)</li> |
| 3077 | </ul> |
| 3078 | |
| 3079 | <p>Note that the thread safety cannot be ensured for multiple threads sharing |
| 3080 | the same document, the locking must be done at the application level, libxml |
| 3081 | exports a basic mutex and reentrant mutexes API in <libxml/threads.h>. |
| 3082 | The parts of the library checked for thread safety are:</p> |
| 3083 | <ul> |
| 3084 | <li>concurrent loading</li> |
| 3085 | <li>file access resolution</li> |
| 3086 | <li>catalog access</li> |
| 3087 | <li>catalog building</li> |
| 3088 | <li>entities lookup/accesses</li> |
| 3089 | <li>validation</li> |
| 3090 | <li>global variables per-thread override</li> |
| 3091 | <li>memory handling</li> |
| 3092 | </ul> |
| 3093 | |
| 3094 | <p>XPath is supposed to be thread safe now, but this wasn't tested |
| 3095 | seriously.</p> |
| 3096 | |
Daniel Veillard | 3500838 | 1999-10-25 13:15:52 +0000 | [diff] [blame] | 3097 | <h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3098 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3099 | <p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document |
| 3100 | Object Model</em>; this is an API for accessing XML or HTML structured |
| 3101 | documents. Native support for DOM in Gnome is on the way (module gnome-dom), |
| 3102 | and will be based on gnome-xml. This will be a far cleaner interface to |
| 3103 | manipulate XML files within Gnome since it won't expose the internal |
| 3104 | structure.</p> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3105 | |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3106 | <p>The current DOM implementation on top of libxml is the <a |
Daniel Veillard | a47fb3d | 2001-03-25 17:23:49 +0000 | [diff] [blame] | 3107 | href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this |
| 3108 | is a full DOM interface, thanks to Paolo Casarini, check the <a |
| 3109 | href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more |
| 3110 | informations.</p> |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3111 | |
Daniel Veillard | 3500838 | 1999-10-25 13:15:52 +0000 | [diff] [blame] | 3112 | <h2><a name="Example"></a><a name="real">A real example</a></h2> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3113 | |
| 3114 | <p>Here is a real size example, where the actual content of the application |
| 3115 | data is not kept in the DOM tree but uses internal structures. It is based on |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3116 | a proposal to keep a database of jobs related to Gnome, with an XML based |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3117 | storage structure. Here is an <a href="gjobs.xml">XML encoded jobs |
| 3118 | base</a>:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3119 | <pre><?xml version="1.0"?> |
| 3120 | <gjob:Helping xmlns:gjob="http://www.gnome.org/some-location"> |
| 3121 | <gjob:Jobs> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3122 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3123 | <gjob:Job> |
| 3124 | <gjob:Project ID="3"/> |
| 3125 | <gjob:Application>GBackup</gjob:Application> |
| 3126 | <gjob:Category>Development</gjob:Category> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3127 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3128 | <gjob:Update> |
| 3129 | <gjob:Status>Open</gjob:Status> |
| 3130 | <gjob:Modified>Mon, 07 Jun 1999 20:27:45 -0400 MET DST</gjob:Modified> |
| 3131 | <gjob:Salary>USD 0.00</gjob:Salary> |
| 3132 | </gjob:Update> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3133 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3134 | <gjob:Developers> |
| 3135 | <gjob:Developer> |
| 3136 | </gjob:Developer> |
| 3137 | </gjob:Developers> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3138 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3139 | <gjob:Contact> |
| 3140 | <gjob:Person>Nathan Clemons</gjob:Person> |
| 3141 | <gjob:Email>nathan@windsofstorm.net</gjob:Email> |
| 3142 | <gjob:Company> |
| 3143 | </gjob:Company> |
| 3144 | <gjob:Organisation> |
| 3145 | </gjob:Organisation> |
| 3146 | <gjob:Webpage> |
| 3147 | </gjob:Webpage> |
| 3148 | <gjob:Snailmail> |
| 3149 | </gjob:Snailmail> |
| 3150 | <gjob:Phone> |
| 3151 | </gjob:Phone> |
| 3152 | </gjob:Contact> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3153 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3154 | <gjob:Requirements> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3155 | The program should be released as free software, under the GPL. |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3156 | </gjob:Requirements> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3157 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3158 | <gjob:Skills> |
| 3159 | </gjob:Skills> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3160 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3161 | <gjob:Details> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3162 | A GNOME based system that will allow a superuser to configure |
| 3163 | compressed and uncompressed files and/or file systems to be backed |
| 3164 | up with a supported media in the system. This should be able to |
| 3165 | perform via find commands generating a list of files that are passed |
| 3166 | to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine |
| 3167 | or via operations performed on the filesystem itself. Email |
| 3168 | notification and GUI status display very important. |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3169 | </gjob:Details> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3170 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3171 | </gjob:Job> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3172 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3173 | </gjob:Jobs> |
| 3174 | </gjob:Helping></pre> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3175 | |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3176 | <p>While loading the XML file into an internal DOM tree is a matter of |
| 3177 | calling only a couple of functions, browsing the tree to gather the ata and |
| 3178 | generate the internal structures is harder, and more error prone.</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3179 | |
| 3180 | <p>The suggested principle is to be tolerant with respect to the input |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3181 | structure. For example, the ordering of the attributes is not significant, |
| 3182 | the XML specification is clear about it. It's also usually a good idea not to |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 3183 | depend on the order of the children of a given node, unless it really makes |
| 3184 | things harder. Here is some code to parse the information for a person:</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3185 | <pre>/* |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3186 | * A person record |
| 3187 | */ |
| 3188 | typedef struct person { |
| 3189 | char *name; |
| 3190 | char *email; |
| 3191 | char *company; |
| 3192 | char *organisation; |
| 3193 | char *smail; |
| 3194 | char *webPage; |
| 3195 | char *phone; |
| 3196 | } person, *personPtr; |
| 3197 | |
| 3198 | /* |
| 3199 | * And the code needed to parse it |
| 3200 | */ |
| 3201 | personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) { |
| 3202 | personPtr ret = NULL; |
| 3203 | |
| 3204 | DEBUG("parsePerson\n"); |
| 3205 | /* |
| 3206 | * allocate the struct |
| 3207 | */ |
| 3208 | ret = (personPtr) malloc(sizeof(person)); |
| 3209 | if (ret == NULL) { |
| 3210 | fprintf(stderr,"out of memory\n"); |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3211 | return(NULL); |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3212 | } |
| 3213 | memset(ret, 0, sizeof(person)); |
| 3214 | |
| 3215 | /* We don't care what the top level element name is */ |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3216 | cur = cur->xmlChildrenNode; |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3217 | while (cur != NULL) { |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3218 | if ((!strcmp(cur->name, "Person")) && (cur->ns == ns)) |
| 3219 | ret->name = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); |
| 3220 | if ((!strcmp(cur->name, "Email")) && (cur->ns == ns)) |
| 3221 | ret->email = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); |
| 3222 | cur = cur->next; |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3223 | } |
| 3224 | |
| 3225 | return(ret); |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3226 | }</pre> |
| 3227 | |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 3228 | <p>Here are a couple of things to notice:</p> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3229 | <ul> |
Daniel Veillard | 91e9d58 | 2001-02-26 07:31:12 +0000 | [diff] [blame] | 3230 | <li>Usually a recursive parsing style is the more convenient one: XML data |
| 3231 | is by nature subject to repetitive constructs and usually exibits highly |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3232 | stuctured patterns.</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3233 | <li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>, |
| 3234 | i.e. the pointer to the global XML document and the namespace reserved to |
| 3235 | the application. Document wide information are needed for example to |
| 3236 | decode entities and it's a good coding practice to define a namespace for |
| 3237 | your application set of data and test that the element and attributes |
| 3238 | you're analyzing actually pertains to your application space. This is |
| 3239 | done by a simple equality test (cur->ns == ns).</li> |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 3240 | <li>To retrieve text and attributes value, you can use the function |
| 3241 | <em>xmlNodeListGetString</em> to gather all the text and entity reference |
| 3242 | nodes generated by the DOM output and produce an single text string.</li> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3243 | </ul> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3244 | |
| 3245 | <p>Here is another piece of code used to parse another level of the |
| 3246 | structure:</p> |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3247 | <pre>#include <libxml/tree.h> |
Daniel Veillard | 361d845 | 2000-04-03 19:48:13 +0000 | [diff] [blame] | 3248 | /* |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3249 | * a Description for a Job |
| 3250 | */ |
| 3251 | typedef struct job { |
| 3252 | char *projectID; |
| 3253 | char *application; |
| 3254 | char *category; |
| 3255 | personPtr contact; |
| 3256 | int nbDevelopers; |
| 3257 | personPtr developers[100]; /* using dynamic alloc is left as an exercise */ |
| 3258 | } job, *jobPtr; |
| 3259 | |
| 3260 | /* |
| 3261 | * And the code needed to parse it |
| 3262 | */ |
| 3263 | jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) { |
| 3264 | jobPtr ret = NULL; |
| 3265 | |
| 3266 | DEBUG("parseJob\n"); |
| 3267 | /* |
| 3268 | * allocate the struct |
| 3269 | */ |
| 3270 | ret = (jobPtr) malloc(sizeof(job)); |
| 3271 | if (ret == NULL) { |
| 3272 | fprintf(stderr,"out of memory\n"); |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3273 | return(NULL); |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3274 | } |
| 3275 | memset(ret, 0, sizeof(job)); |
| 3276 | |
| 3277 | /* We don't care what the top level element name is */ |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3278 | cur = cur->xmlChildrenNode; |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3279 | while (cur != NULL) { |
| 3280 | |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3281 | if ((!strcmp(cur->name, "Project")) && (cur->ns == ns)) { |
| 3282 | ret->projectID = xmlGetProp(cur, "ID"); |
| 3283 | if (ret->projectID == NULL) { |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3284 | fprintf(stderr, "Project has no ID\n"); |
| 3285 | } |
| 3286 | } |
Daniel Veillard | 60979bd | 2000-07-10 12:17:33 +0000 | [diff] [blame] | 3287 | if ((!strcmp(cur->name, "Application")) && (cur->ns == ns)) |
| 3288 | ret->application = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); |
| 3289 | if ((!strcmp(cur->name, "Category")) && (cur->ns == ns)) |
| 3290 | ret->category = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1); |
| 3291 | if ((!strcmp(cur->name, "Contact")) && (cur->ns == ns)) |
| 3292 | ret->contact = parsePerson(doc, ns, cur); |
| 3293 | cur = cur->next; |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3294 | } |
| 3295 | |
| 3296 | return(ret); |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3297 | }</pre> |
Daniel Veillard | 14fff06 | 1999-06-22 21:49:07 +0000 | [diff] [blame] | 3298 | |
Daniel Veillard | ec70e91 | 2001-02-26 20:10:45 +0000 | [diff] [blame] | 3299 | <p>Once you are used to it, writing this kind of code is quite simple, but |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3300 | boring. Ultimately, it could be possble to write stubbers taking either C |
| 3301 | data structure definitions, a set of XML examples or an XML DTD and produce |
| 3302 | the code needed to import and export the content between C data and XML |
| 3303 | storage. This is left as an exercise to the reader :-)</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3304 | |
Daniel Veillard | 6f0adb5 | 2000-07-03 11:41:26 +0000 | [diff] [blame] | 3305 | <p>Feel free to use <a href="example/gjobread.c">the code for the full C |
| 3306 | parsing example</a> as a template, it is also available with Makefile in the |
| 3307 | Gnome CVS base under gnome-xml/example</p> |
Daniel Veillard | b05deb7 | 1999-08-10 19:04:08 +0000 | [diff] [blame] | 3308 | |
Daniel Veillard | c310d56 | 2000-06-23 18:32:15 +0000 | [diff] [blame] | 3309 | <h2><a name="Contributi">Contributions</a></h2> |
| 3310 | <ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 3311 | <li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of |
| 3312 | patches, Gary Pennington worked on the validation API, threading support |
| 3313 | and Solaris port.</li> |
| 3314 | <li>John Fleck helps maintaining the documentation and man pages.</li> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 3315 | <li><a href="mailto:ari@lusis.org">Ari Johnson</a> |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 3316 | provides a C++ wrapper for libxml:<br> |
Daniel Veillard | c6271d2 | 2001-10-27 07:50:58 +0000 | [diff] [blame] | 3317 | Website: <a |
| 3318 | href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a><br> |
| 3319 | Download: <a |
Daniel Veillard | 5109531 | 2001-10-28 18:51:57 +0000 | [diff] [blame] | 3320 | href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3321 | <li><a href="mailto:izlatkovic@daenet.de">Igor Zlatkovic</a> |
| 3322 | is now the maintainer of the Windows port, <a |
Daniel Veillard | 9518953 | 2001-07-26 18:30:26 +0000 | [diff] [blame] | 3323 | href="http://www.fh-frankfurt.de/~igor/projects/libxml/index.html">he |
| 3324 | provides binaries</a></li> |
Daniel Veillard | c948420 | 2001-10-24 12:35:52 +0000 | [diff] [blame] | 3325 | <li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> |
Daniel Veillard | db9dfd9 | 2001-11-26 17:25:02 +0000 | [diff] [blame] | 3326 | provides <a href="http://garypennington.net/libxml2/">Solaris |
Daniel Veillard | 0a702dc | 2001-10-19 14:50:57 +0000 | [diff] [blame] | 3327 | binaries</a></li> |
Daniel Veillard | e356c28 | 2001-03-10 12:32:04 +0000 | [diff] [blame] | 3328 | <li><a |
| 3329 | href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3330 | Sergeant</a> |
| 3331 | developped <a href="http://axkit.org/download/">XML::LibXSLT</a>, a perl |
| 3332 | wrapper for libxml2/libxslt as part of the <a |
| 3333 | href="http://axkit.com/">AxKit XML application server</a></li> |
| 3334 | <li><a href="mailto:fnatter@gmx.net">Felix Natter</a> |
| 3335 | and <a href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a |
Daniel Veillard | ca98976 | 2001-06-23 17:39:29 +0000 | [diff] [blame] | 3336 | href="libxml-doc.el">an emacs module</a> to lookup libxml(2) functions |
Daniel Veillard | 3f6f7f6 | 2000-06-30 17:58:25 +0000 | [diff] [blame] | 3337 | documentation</li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3338 | <li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> |
| 3339 | provided <a href="http://xmlsoft.org/messages/0488.html">man |
| 3340 | pages</a></li> |
Daniel Veillard | 5168dbf | 2001-07-07 00:18:23 +0000 | [diff] [blame] | 3341 | <li>there is a module for <a |
| 3342 | href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support |
| 3343 | in OpenNSD/AOLServer</a></li> |
Daniel Veillard | 3d6ae1c | 2001-08-15 13:12:39 +0000 | [diff] [blame] | 3344 | <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> |
| 3345 | provides libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers |
| 3346 | for Python</a></li> |
Daniel Veillard | 1aadc44 | 2001-11-28 13:10:32 +0000 | [diff] [blame] | 3347 | <li>Petr Kozelka provides <a |
| 3348 | href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue |
| 3349 | libxml2</a> with Kylix and Delphi and other Pascal compilers</li> |
Daniel Veillard | c310d56 | 2000-06-23 18:32:15 +0000 | [diff] [blame] | 3350 | </ul> |
| 3351 | |
Daniel Veillard | c8eab3a | 1999-09-04 18:27:23 +0000 | [diff] [blame] | 3352 | <p></p> |
Daniel Veillard | ccb0963 | 1998-10-27 06:21:04 +0000 | [diff] [blame] | 3353 | </body> |
| 3354 | </html> |