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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	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	5	<title>The XML C parser and toolkit for Gnome</title>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	6	<meta name="GENERATOR" content="amaya 5.1">
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	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	11	<h1 align="center">The XML C parser and toolkit 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
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	20	<p>Libxml2 is the XML C parser and toolkit developed for the Gnome project.
				21	XML itself is a metalanguage to design markup languages, i.e. text language
				22	where semantic and structure are added to the content using extra "markup"
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	23	information enclosed between angle brackets. HTML is the most well-known
Daniel Veillard	1eb2424	2002-03-18 11:33:03 +0000	[diff] [blame]	24	markup language. Though the library is written in C <a href="python.html">a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	25	variety of language bindings</a> make it available in other environments.</p>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	26
Daniel Veillard	710823b	2003-03-04 10:05:52 +0000	[diff] [blame]	27	<p>Libxml2 is known to be very portable, the library should build and work
				28	without serious troubles on a variety of systems (Linux, Unix, Windows,
				29	CygWin, MacOS, MacOS X, RISC Os, OS/2, VMS, QNX, MVS, ...)</p>
				30
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	31	<p>Libxml2 implements a number of existing standards related to markup
				32	languages:</p>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	33	<ul>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	34	<li>the XML standard: <a
				35	href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a></li>
				36	<li>Namespaces in XML: <a
				37	href="http://www.w3.org/TR/REC-xml-names/">http://www.w3.org/TR/REC-xml-names/</a></li>
				38	<li>XML Base: <a
				39	href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a></li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	40	<li><a href="http://www.cis.ohio-state.edu/rfc/rfc2396.txt">RFC 2396</a> :
				41	Uniform Resource Identifiers <a
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	42	href="http://www.ietf.org/rfc/rfc2396.txt">http://www.ietf.org/rfc/rfc2396.txt</a></li>
				43	<li>XML Path Language (XPath) 1.0: <a
				44	href="http://www.w3.org/TR/xpath">http://www.w3.org/TR/xpath</a></li>
				45	<li>HTML4 parser: <a
				46	href="http://www.w3.org/TR/html401/">http://www.w3.org/TR/html401/</a></li>
				47	<li>most of XML Pointer Language (XPointer) Version 1.0: <a
				48	href="http://www.w3.org/TR/xptr">http://www.w3.org/TR/xptr</a></li>
				49	<li>XML Inclusions (XInclude) Version 1.0: <a
				50	href="http://www.w3.org/TR/xinclude/">http://www.w3.org/TR/xinclude/</a></li>
				51	<li>[ISO-8859-1], <a
				52	href="http://www.cis.ohio-state.edu/rfc/rfc2044.txt">rfc2044</a> [UTF-8]
				53	and <a href="http://www.cis.ohio-state.edu/rfc/rfc2781.txt">rfc2781</a>
				54	[UTF-16] core encodings</li>
				55	<li>part of SGML Open Technical Resolution TR9401:1997</li>
				56	<li>XML Catalogs Working Draft 06 August 2001: <a
				57	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	5c39654	2002-03-15 07:57:50 +0000	[diff] [blame]	58	<li>Canonical XML Version 1.0: <a
				59	href="http://www.w3.org/TR/xml-c14n">http://www.w3.org/TR/xml-c14n</a>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	60	and the Exclusive XML Canonicalization CR draft <a
				61	href="http://www.w3.org/TR/xml-exc-c14n">http://www.w3.org/TR/xml-exc-c14n</a></li>
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	62	<li>Relax NG Committee Specification 3 December 2001 <a
				63	href="http://www.oasis-open.org/committees/relax-ng/spec-20011203.html">http://www.oasis-open.org/committees/relax-ng/spec-20011203.html</a></li>
Daniel Veillard	f83a2c7	2003-04-08 13:48:40 +0000	[diff] [blame]	64	<li>W3C XML Schemas Part 2: Datatypes <a
				65	href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">REC 02 May
				66	2001</a> except the base64Binary and hexBinary types</li>
Daniel Veillard	9698445	2000-08-31 13:50:12 +0000	[diff] [blame]	67	</ul>
				68
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	69	<p>In most cases libxml2 tries to implement the specifications in a relatively
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	70	strictly compliant way. As of release 2.4.16, libxml2 passes all 1800+ tests
				71	from the <a
Daniel Veillard	a539356	2002-02-20 11:40:49 +0000	[diff] [blame]	72	href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests
				73	Suite</a>.</p>
Daniel Veillard	5b16f58	2002-02-20 11:38:46 +0000	[diff] [blame]	74
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	75	<p>To some extent libxml2 provides support for the following additional
				76	specifications but doesn't claim to implement them completely:</p>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	77	<ul>
				78	<li>Document Object Model (DOM) <a
				79	href="http://www.w3.org/TR/DOM-Level-2-Core/">http://www.w3.org/TR/DOM-Level-2-Core/</a>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	80	it doesn't implement the API itself, gdome2 does this on top of
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	81	libxml2</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	82	<li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> :
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	83	libxml2 implements a basic FTP client code</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	84	<li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> :
				85	HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	86	<li>SAX: a minimal SAX implementation compatible with early expat
				87	versions</li>
				88	<li>DocBook SGML v4: libxml2 includes a hackish parser to transition to
				89	XML</li>
				90	</ul>
				91
Daniel Veillard	f83a2c7	2003-04-08 13:48:40 +0000	[diff] [blame]	92	<p>A partial implementation of <a
				93	href="http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/">XML Schemas Part
				94	1: Structure</a> is being worked on but it would be far too early to make any
				95	conformance statement about it at the moment.</p>
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	96
Daniel Veillard	9698445	2000-08-31 13:50:12 +0000	[diff] [blame]	97	<p>Separate documents:</p>
				98	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	99	<li><a href="http://xmlsoft.org/XSLT/">the libxslt page</a> providing an
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	100	implementation of XSLT 1.0 and common extensions like EXSLT for
				101	libxml2</li>
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	102	<li><a href="http://www.cs.unibo.it/~casarini/gdome2/">the gdome2 page</a>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	103	: a standard DOM2 implementation for libxml2</li>
				104	<li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an
				105	implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML
				106	Digital Signature</a> for libxml2</li>
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	107	<li>also check the related links section below for more related and active
				108	projects.</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	109	</ul>
				110
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	111	<p>Results of the <a
				112	href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench
				113	benchmark</a> on sourceforge 19 March 2003 (smaller is better):</p>
Daniel Veillard	d8da01c	2003-03-24 15:58:23 +0000	[diff] [blame]	114
				115	<p align="center"><img src="benchmark.gif"
				116	alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p>
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	117
Daniel Veillard	e166254	2002-08-28 11:50:59 +0000	[diff] [blame]	118	<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p>
				119
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	120	<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	121
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	122	<p>This document describes libxml, the <a
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	123	href="http://www.w3.org/XML/">XML</a> C parser and toolkit developed for the <a
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	124	href="http://www.gnome.org/">Gnome</a> project. <a
				125	href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
				126	structured documents/data.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	127
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	128	<p>Here are some key points about libxml:</p>
				129	<ul>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	130	<li>Libxml2 exports Push (progressive) and Pull (blocking) type parser
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	131	interfaces for both XML and HTML.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	132	<li>Libxml2 can do DTD validation at parse time, using a parsed document
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	133	instance, or with an arbitrary DTD.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	134	<li>Libxml2 includes complete <a
Daniel Veillard	8c2ecaf	2001-07-10 17:53:07 +0000	[diff] [blame]	135	href="http://www.w3.org/TR/xpath">XPath</a>, <a
				136	href="http://www.w3.org/TR/xptr">XPointer</a> and <a
				137	href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	138	<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]	139	sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	140	Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	141	<li>Basic support for HTTP and FTP client allowing applications to fetch
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	142	remote resources.</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	143	<li>The design is modular, most of the extensions can be compiled out.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	144	<li>The internal document representation is as close as possible to the <a
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	145	href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	146	<li>Libxml2 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]	147	like interface</a>; the interface is designed to be compatible with <a
				148	href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	149	<li>This library is released under the <a
				150	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	151	License</a>. See the Copyright file in the distribution for the precise
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	152	wording.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	153	</ul>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	154
Daniel Veillard	e0c1d72	2001-03-21 10:28:36 +0000	[diff] [blame]	155	<p>Warning: unless you are forced to because your application links with a
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	156	Gnome-1.X library requiring it, <strong><span
Daniel Veillard	e0c1d72	2001-03-21 10:28:36 +0000	[diff] [blame]	157	style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
				158	libxml2</p>
				159
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	160	<h2><a name="FAQ">FAQ</a></h2>
				161
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	162	<p>Table of Contents:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	163	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	164	<li><a href="FAQ.html#License">License(s)</a></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	165	<li><a href="FAQ.html#Installati">Installation</a></li>
				166	<li><a href="FAQ.html#Compilatio">Compilation</a></li>
				167	<li><a href="FAQ.html#Developer">Developer corner</a></li>
				168	</ul>
				169
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	170	<h3><a name="License">License</a>(s)</h3>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	171	<ol>
				172	<li><em>Licensing Terms for libxml</em>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	173	<p>libxml2 is released under the <a
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	174	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	175	License</a>; see the file Copyright in the distribution for the precise
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	176	wording</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	177	</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	178	<li><em>Can I embed libxml2 in a proprietary application ?</em>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	179	<p>Yes. The MIT License allows you to keep proprietary the changes you
				180	made to libxml, but it would be graceful to send-back bug fixes and
				181	improvements as patches for possible incorporation in the main
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	182	development tree.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	183	</li>
				184	</ol>
				185
				186	<h3><a name="Installati">Installation</a></h3>
				187	<ol>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	188	<li><strong><span style="background-color: #FF0000">Do
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	189	Not Use libxml1</span></strong>, use libxml2</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	190	<li><em>Where can I get libxml</em> ?
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	191	<p>The original distribution comes from <a
				192	href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
Daniel Veillard	6581e1b	2003-02-09 22:21:43 +0000	[diff] [blame]	193	href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.5/">gnome.org</a></p>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	194	<p>Most Linux and BSD distributions include libxml, this is probably the
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	195	safer way for end-users to use libxml.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	196	<p>David Doolin provides precompiled Windows versions at <a
				197	href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
				198	</li>
				199	<li><em>I see libxml and libxml2 releases, which one should I install ?</em>
				200	<ul>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	201	<li>If you are not constrained by backward compatibility issues with
				202	existing applications, install libxml2 only</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	203	<li>If you are not doing development, you can safely install both.
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	204	Usually the packages <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	205	href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
				206	href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	207	compatible (this is not the case for development packages).</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	208	<li>If you are a developer and your system provides separate packaging
				209	for shared libraries and the development components, it is possible
				210	to install libxml and libxml2, and also <a
				211	href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
				212	and <a
				213	href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
				214	too for libxml2 >= 2.3.0</li>
				215	<li>If you are developing a new application, please develop against
				216	libxml2(-devel)</li>
				217	</ul>
				218	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	219	<li><em>I can't install the libxml package, it conflicts with libxml0</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	220	<p>You probably have an old libxml0 package used to provide the shared
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	221	library for libxml.so.0, you can probably safely remove it. The libxml
				222	packages provided on <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	223	href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provide
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	224	libxml.so.0</p>
				225	</li>
				226	<li><em>I can't install the libxml(2) RPM package due to failed
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	227	dependencies</em>
				228	<p>The most generic solution is to re-fetch the latest src.rpm , and
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	229	rebuild it locally with</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	230	<p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	231	<p>If everything goes well it will generate two binary rpm packages (one
				232	providing the shared libs and xmllint, and the other one, the -devel
				233	package, providing includes, static libraries and scripts needed to build
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	234	applications with libxml(2)) that you can install locally.</p>
				235	</li>
				236	</ol>
				237
				238	<h3><a name="Compilatio">Compilation</a></h3>
				239	<ol>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	240	<li><em>What is the process to compile libxml2 ?</em>
				241	<p>As most UNIX libraries libxml2 follows the "standard":</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	242	<p><code>gunzip -c xxx.tar.gz \| tar xvf -</code></p>
				243	<p><code>cd libxml-xxxx</code></p>
				244	<p><code>./configure --help</code></p>
				245	<p>to see the options, then the compilation/installation proper</p>
				246	<p><code>./configure [possible options]</code></p>
				247	<p><code>make</code></p>
				248	<p><code>make install</code></p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	249	<p>At that point you may have to rerun ldconfig or a similar utility to
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	250	update your list of installed shared libs.</p>
				251	</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	252	<li><em>What other libraries are needed to compile/install libxml2 ?</em>
				253	<p>Libxml2 does not require any other library, the normal C ANSI API
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	254	should be sufficient (please report any violation to this rule you may
				255	find).</p>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	256	<p>However if found at configuration time libxml2 will detect and use the
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	257	following libs:</p>
				258	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	259	<li><a href="http://www.info-zip.org/pub/infozip/zlib/">libz</a> : a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	260	highly portable and available widely compression library.</li>
				261	<li>iconv: a powerful character encoding conversion library. It is
				262	included by default in recent glibc libraries, so it doesn't need to
				263	be installed specifically on Linux. It now seems a <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	264	href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
				265	of the official UNIX</a> specification. Here is one <a
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	266	href="http://www.gnu.org/software/libiconv/">implementation of the
				267	library</a> which source can be found <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	268	href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
				269	</ul>
				270	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	271	<li><em>Make check fails on some platforms</em>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	272	<p>Sometimes the regression tests' results don't completely match the
				273	value produced by the parser, and the makefile uses diff to print the
				274	delta. On some platforms the diff return breaks the compilation process;
				275	if the diff is small this is probably not a serious problem.</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	276	<p>Sometimes (especially on Solaris) make checks fail due to limitations
Daniel Veillard	e46182c	2002-02-12 14:29:11 +0000	[diff] [blame]	277	in make. Try using GNU-make instead.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	278	</li>
				279	<li><em>I use the CVS version and there is no configure script</em>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	280	<p>The configure script (and other Makefiles) are generated. Use the
				281	autogen.sh script to regenerate the configure script and Makefiles,
				282	like:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	283	<p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
				284	</li>
				285	<li><em>I have troubles when running make tests with gcc-3.0</em>
				286	<p>It seems the initial release of gcc-3.0 has a problem with the
				287	optimizer which miscompiles the URI module. Please use another
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	288	compiler.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	289	</li>
				290	</ol>
				291
				292	<h3><a name="Developer">Developer</a> corner</h3>
				293	<ol>
Daniel Veillard	93d9525	2003-04-29 20:25:40 +0000	[diff] [blame]	294	<li><em>Troubles compiling or linking programs using libxml2</em>
				295	<p>Usually the problem comes from the fact that the compiler doesn't get
				296	the right compilation or linking flags. There is a small shell script
				297	<code>xml2-config</code> which is installed as part of libxml2 usual
				298	install process which provides those flags. Use </p>
				299	<p><code>xml2-config --cflags</code></p>
				300	<p>to get the compilation flags and</p>
				301	<p><code>xml2-config --libs</code></p>
				302	<p>to get the linker flags. Usually this is done directly from the
				303	Makefile as:</p>
				304	<p><code>CFLAGS=`xml2-config --cflags`</code></p>
				305	<p><code>LIBS=`xml2-config --libs`</code></p>
				306	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	307	<li><em>xmlDocDump() generates output on one line.</em>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	308	<p>Libxml2 will not <strong>invent</strong> spaces in the content of a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	309	document since <strong>all spaces in the content of a document are
				310	significant</strong>. If you build a tree from the API and want
				311	indentation:</p>
				312	<ol>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	313	<li>the correct way is to generate those yourself too.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	314	<li>the dangerous way is to ask libxml2 to add those blanks to your
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	315	content <strong>modifying the content of your document in the
				316	process</strong>. The result may not be what you expect. There is
				317	<strong>NO</strong> way to guarantee that such a modification won't
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	318	affect other parts of the content of your document. See <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	319	href="http://xmlsoft.org/html/libxml-parser.html#XMLKEEPBLANKSDEFAULT">xmlKeepBlanksDefault
				320	()</a> and <a
				321	href="http://xmlsoft.org/html/libxml-tree.html#XMLSAVEFORMATFILE">xmlSaveFormatFile
				322	()</a></li>
				323	</ol>
				324	</li>
				325	<li>Extra nodes in the document:
				326	<p><em>For a XML file as below:</em></p>
				327	<pre><?xml version="1.0"?>
				328	<PLAN xmlns="http://www.argus.ca/autotest/1.0/">
				329	<NODE CommFlag="0"/>
				330	<NODE CommFlag="1"/>
				331	</PLAN></pre>
				332	<p><em>after parsing it with the function
				333	pxmlDoc=xmlParseFile(...);</em></p>
				334	<p><em>I want to the get the content of the first node (node with the
				335	CommFlag="0")</em></p>
				336	<p><em>so I did it as following;</em></p>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	337	<pre>xmlNodePtr pnode;
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	338	pnode=pxmlDoc->children->children;</pre>
				339	<p><em>but it does not work. If I change it to</em></p>
				340	<pre>pnode=pxmlDoc->children->children->next;</pre>
				341	<p><em>then it works. Can someone explain it to me.</em></p>
				342	<p></p>
				343	<p>In XML all characters in the content of the document are significant
				344	<strong>including blanks and formatting line breaks</strong>.</p>
				345	<p>The extra nodes you are wondering about are just that, text nodes with
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	346	the formatting spaces which are part of the document but that people tend
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	347	to forget. There is a function <a
				348	href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
				349	()</a> to remove those at parse time, but that's an heuristic, and its
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	350	use should be limited to cases where you are certain there is no
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	351	mixed-content in the document.</p>
				352	</li>
				353	<li><em>I get compilation errors of existing code like when accessing
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	354	<strong>root</strong> or <strong>child fields</strong> of nodes.</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	355	<p>You are compiling code developed for libxml version 1 and using a
				356	libxml2 development environment. Either switch back to libxml v1 devel or
				357	even better fix the code to compile with libxml2 (or both) by <a
				358	href="upgrade.html">following the instructions</a>.</p>
				359	</li>
				360	<li><em>I get compilation errors about non existing
				361	<strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	362	fields.</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	363	<p>The source code you are using has been <a
				364	href="upgrade.html">upgraded</a> to be able to compile with both libxml
				365	and libxml2, but you need to install a more recent version:
				366	libxml(-devel) >= 1.8.8 or libxml2(-devel) >= 2.1.0</p>
				367	</li>
				368	<li><em>XPath implementation looks seriously broken</em>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	369	<p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to
				370	a recent version, there are no known bugs in the current version.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	371	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	372	<li><em>The example provided in the web page does not compile.</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	373	<p>It's hard to maintain the documentation in sync with the code
				374	<grin/> ...</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	375	<p>Check the previous points 1/ and 2/ raised before, and please send
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	376	patches.</p>
				377	</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	378	<li><em>Where can I get more examples and information than privoded on the
				379	web page?</em>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	380	<p>Ideally a libxml2 book would be nice. I have no such plan ... But you
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	381	can:</p>
				382	<ul>
				383	<li>check more deeply the <a href="html/libxml-lib.html">existing
				384	generated doc</a></li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	385	<li>look for examples of use for libxml2 function using the Gnome code.
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	386	For example the following will query the full Gnome CVS base for the
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	387	use of the <strong>xmlAddChild()</strong> function:
				388	<p><a
				389	href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
				390	<p>This may be slow, a large hardware donation to the gnome project
				391	could cure this :-)</p>
				392	</li>
				393	<li><a
				394	href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Browse
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	395	the libxml2 source</a> , I try to write code as clean and documented
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	396	as possible, so looking at it may be helpful. In particular the code
				397	of xmllint.c and of the various testXXX.c test programs should
				398	provide good examples of how to do things with the library.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	399	</ul>
				400	</li>
				401	<li>What about C++ ?
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	402	<p>libxml2 is written in pure C in order to allow easy reuse on a number
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	403	of platforms, including embedded systems. I don't intend to convert to
				404	C++.</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	405	<p>There are however a few C++ wrappers which may fulfill your needs:</p>
Daniel Veillard	9b6fd30	2002-05-13 12:06:47 +0000	[diff] [blame]	406	<ul>
				407	<li>by Ari Johnson <ari@btigate.com>:
				408	<p>Website: <a
				409	href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
				410	<p>Download: <a
				411	href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
				412	</li>
				413	<li>by Peter Jones <pjones@pmade.org>
				414	<p>Website: <a
				415	href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
				416	</li>
				417	</ul>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	418	</li>
				419	<li>How to validate a document a posteriori ?
				420	<p>It is possible to validate documents which had not been validated at
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	421	initial parsing time or documents which have been built from scratch
				422	using the API. Use the <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	423	href="http://xmlsoft.org/html/libxml-valid.html#XMLVALIDATEDTD">xmlValidateDtd()</a>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	424	function. It is also possible to simply add a DTD to an existing
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	425	document:</p>
				426	<pre>xmlDocPtr doc; /* your existing document */
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	427	xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
				428
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	429	dtd->name = xmlStrDup((xmlChar)"root_name"); / use the given root */
				430
				431	doc->intSubset = dtd;
				432	if (doc->children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
				433	else xmlAddPrevSibling(doc->children, (xmlNodePtr)dtd);
				434	</pre>
				435	</li>
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	436	<li>So what is this funky "xmlChar" used all the time?
				437	<p>It is a null terminated sequence of utf-8 characters. And only utf-8!
				438	You need to convert strings encoded in different ways to utf-8 before
				439	passing them to the API. This can be accomplished with the iconv library
				440	for instance.</p>
John Fleck	61f6fb6	2002-10-31 15:23:29 +0000	[diff] [blame]	441	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	442	<li>etc ...</li>
				443	</ol>
				444
				445	<p></p>
				446
Daniel Veillard	1177ca4	2003-04-26 22:29:54 +0000	[diff] [blame]	447	<h2><a name="Documentat">Developer Documentation</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	448
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	449	<p>There are several on-line resources related to using libxml:</p>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	450	<ol>
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	451	<li>Use the <a href="search.php">search engine</a> to lookup
				452	informations.</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	453	<li>Check the <a href="FAQ.html">FAQ.</a></li>
Daniel Veillard	c19fccc	2000-07-03 11:52:01 +0000	[diff] [blame]	454	<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]	455	documentation</a> automatically extracted from code comments (using <a
				456	href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gtk-doc">gtk
				457	doc</a>).</li>
Daniel Veillard	8d86964	2000-07-14 12:12:59 +0000	[diff] [blame]	458	<li>Look at the documentation about <a href="encoding.html">libxml
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	459	internationalization support</a>.</li>
Daniel Veillard	bc66f85	2002-01-14 09:49:20 +0000	[diff] [blame]	460	<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]	461	examples</a> on how to use libxml.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	462	<li>John Fleck's libxml2 tutorial: <a href="tutorial/index.html">html</a> or
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	463	<a href="tutorial/xmltutorial.pdf">pdf</a>.</li>
Daniel Veillard	1177ca4	2003-04-26 22:29:54 +0000	[diff] [blame]	464	<li>If you need to parse large files, check the <a
				465	href="xmlreader.html">xmlReader</a> API tutorial</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	466	<li><a href="mailto:james@daa.com.au">James Henstridge</a> wrote <a
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	467	href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
				468	documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	469	<li>George Lebl wrote <a
				470	href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	471	for IBM developerWorks</a> about using libxml.</li>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	472	<li>Check <a href="http://cvs.gnome.org/lxr/source/gnome-xml/TODO">the TODO
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	473	file</a>.</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	474	<li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>
				475	description. If you are starting a new project using libxml you should
				476	really use the 2.x version.</li>
Daniel Veillard	845cce4	2002-01-09 11:51:37 +0000	[diff] [blame]	477	<li>And don't forget to look at the <a
				478	href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	479	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	480
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	481	<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	482
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	483	<p>Well, bugs or missing features are always possible, and I will make a
				484	point of fixing them in a timely fashion. The best way to report a bug is to
				485	use the <a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	486	bug tracking database</a> (make sure to use the "libxml2" module name). I
				487	look at reports there regularly and it's good to have a reminder when a bug
				488	is still open. Be sure to specify that the bug is for the package libxml2.</p>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	489
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	490	<p>There is also a mailing-list <a
Daniel Veillard	3197f16	2001-04-04 00:40:08 +0000	[diff] [blame]	491	href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
				492	href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	493	href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
				494	please visit the <a
				495	href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
				496	follow the instructions. <strong>Do not send code, I won't debug it</strong>
				497	(but patches are really appreciated!).</p>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	498
Daniel Veillard	008186f	2001-09-13 14:24:44 +0000	[diff] [blame]	499	<p>Check the following <strong><span style="color: #FF0000">before
				500	posting</span></strong>:</p>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	501	<ul>
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	502	<li>Read the <a href="FAQ.html">FAQ</a> and <a href="search.php">use the
Daniel Veillard	a37aab8	2003-06-09 09:10:36 +0000	[diff] [blame]	503	search engine</a> to get information related to your problem.</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	504	<li>Make sure you are <a href="ftp://xmlsoft.org/">using a recent
				505	version</a>, and that the problem still shows up in a recent version.</li>
				506	<li>Check the <a href="http://mail.gnome.org/archives/xml/">list
				507	archives</a> to see if the problem was reported already. In this case
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	508	there is probably a fix available, similarly check the <a
Daniel Veillard	e7ead2d	2001-08-22 23:44:09 +0000	[diff] [blame]	509	href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	510	open bugs</a>.</li>
				511	<li>Make sure you can reproduce the bug with xmllint or one of the test
				512	programs found in source in the distribution.</li>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	513	<li>Please send the command showing the error as well as the input (as an
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	514	attachment)</li>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	515	</ul>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	516
Daniel Veillard	a37aab8	2003-06-09 09:10:36 +0000	[diff] [blame]	517	<p>Then send the bug with associated information to reproduce it to the <a
Daniel Veillard	33a6780	2001-03-07 09:44:02 +0000	[diff] [blame]	518	href="mailto:xml@gnome.org">xml@gnome.org</a> list; if it's really libxml
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	519	related I will approve it. Please do not send mail to me directly, it makes
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	520	things really hard to track and in some cases I am not the best person to
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	521	answer a given question, ask on the list.</p>
				522
				523	<p>To <span style="color: #E50000">be really clear about support</span>:</p>
				524	<ul>
Daniel Veillard	a37aab8	2003-06-09 09:10:36 +0000	[diff] [blame]	525	<li>Support or help <span style="color: #E50000">requests MUST be sent to
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	526	the list or on bugzilla</span> in case of problems, so that the Question
				527	and Answers can be shared publicly. Failing to do so carries the implicit
				528	message "I want free support but I don't want to share the benefits with
Daniel Veillard	831e8fd	2003-01-25 11:45:34 +0000	[diff] [blame]	529	others" and is not welcome. I will automatically Carbon-Copy the
				530	xml@gnome.org mailing list for any technical reply made about libxml2 or
				531	libxslt.</li>
Daniel Veillard	a37aab8	2003-06-09 09:10:36 +0000	[diff] [blame]	532	<li>There is <span style="color: #E50000">no garantee of support</span>,
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	533	if your question remains unanswered after a week, repost it, making sure
Daniel Veillard	a37aab8	2003-06-09 09:10:36 +0000	[diff] [blame]	534	you gave all the detail needed and the information requested.</li>
				535	<li>Failing to provide information as requested or double checking first
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	536	for prior feedback also carries the implicit message "the time of the
				537	library maintainers is less valuable than my time" and might not be
				538	welcome.</li>
				539	</ul>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	540
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	541	<p>Of course, bugs reported with a suggested patch for fixing them will
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	542	probably be processed faster than those without.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	543
				544	<p>If you're looking for help, a quick look at <a
Daniel Veillard	f7ed336	2001-08-17 12:01:21 +0000	[diff] [blame]	545	href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	546	provide the answer. I usually send source samples when answering libxml2 usage
Daniel Veillard	6f0adb5	2000-07-03 11:41:26 +0000	[diff] [blame]	547	questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	548	documentation</a> is not as polished as I would like (i need to learn more
				549	about DocBook), but it's a good starting point.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	550
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	551	<h2><a name="help">How to help</a></h2>
				552
				553	<p>You can help the project in various ways, the best thing to do first is to
				554	subscribe to the mailing-list as explained before, check the <a
Daniel Veillard	f7ed336	2001-08-17 12:01:21 +0000	[diff] [blame]	555	href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
				556	href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	557	database</a>:</p>
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	558	<ol>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	559	<li>Provide patches when you find problems.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	560	<li>Provide the diffs when you port libxml2 to a new platform. They may not
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	561	be integrated in all cases but help pinpointing portability problems
				562	and</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	563	<li>Provide documentation fixes (either as patches to the code comments or
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	564	as HTML diffs).</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	565	<li>Provide new documentations pieces (translations, examples, etc
				566	...).</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	567	<li>Check the TODO file and try to close one of the items.</li>
				568	<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]	569	provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
				570	</a>before to avoid synchronization problems and check that the suggested
				571	fix will fit in nicely :-)</li>
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	572	</ol>
				573
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	574	<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	575
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	576	<p>The latest versions of libxml2 can be found on <a
Daniel Veillard	20c8cf2	2001-06-26 22:47:36 +0000	[diff] [blame]	577	href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
				578	href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
				579	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]	580	href="ftp://ftp.gnome.org/pub/GNOME/MIRRORS.html">Gnome FTP server</a> either
Daniel Veillard	6581e1b	2003-02-09 22:21:43 +0000	[diff] [blame]	581	as a <a href="ftp://ftp.gnome.org/pub/GNOME/sources/libxml2/2.5/">source
MDT 2002 John Fleck	30c7054	2002-09-24 14:24:54 +0000	[diff] [blame]	582	archive</a><!-- commenting this out because they seem to have disappeared or <a
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	583	href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	584	packages</a> -->
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	585	, Antonin Sprinzl also provide <a href="ftp://gd.tuwien.ac.at/pub/libxml/">a
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	586	mirror in Austria</a>. (NOTE that you need both the <a
Daniel Veillard	c19fccc	2000-07-03 11:52:01 +0000	[diff] [blame]	587	href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
				588	href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard	b46a573	2003-04-08 13:35:48 +0000	[diff] [blame]	589	packages installed to compile applications using libxml.)</p>
				590
				591	<p>Binary ports:</p>
				592	<ul>
				593	<li>Red Hat RPMs for i386 are available directly on <a
				594	href="ftp://xmlsoft.org/">xmlsoft.org</a>, the source RPM will compile on
				595	any architecture supported by Red Hat.</li>
Daniel Veillard	f83a2c7	2003-04-08 13:48:40 +0000	[diff] [blame]	596	<li><p><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a></p>
Daniel Veillard	ce192eb	2003-04-16 15:58:05 +0000	[diff] [blame]	597	is now the maintainer of the Windows port, <a
Daniel Veillard	b46a573	2003-04-08 13:35:48 +0000	[diff] [blame]	598	href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
				599	binaries</a>.</li>
				600	<li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
				601	<a href="http://garypennington.net/libxml2/">Solaris binaries</a>.</li>
				602	<li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a> provides <a
				603	href="http://www.zveno.com/open_source/libxml2xslt.html">Mac Os X
				604	binaries</a>.</li>
				605	<li>The HP-UX porting center provides <a
				606	href="http://hpux.connect.org.uk/hppd/hpux/Gnome/">HP-UX binaries</a></li>
				607	</ul>
				608
				609	<p>If you know other supported binary ports, please <a
				610	href="http://veillard.com/">contact me</a>.</p>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	611
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	612	<p><a name="Snapshot">Snapshot:</a></p>
				613	<ul>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	614	<li>Code from the W3C cvs base gnome-xml <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	615	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]	616	<li>Docs, content of the web site, the list archive included <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	617	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]	618	</ul>
				619
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	620	<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	621
				622	<p>I do accept external contributions, especially if compiling on another
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	623	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]	624	languages have been provided, and can be found in the <a
				625	href="contribs.html">contrib section</a></p>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	626
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	627	<p>Libxml2 is also available from CVS:</p>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	628	<ul>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	629	<li><p>The <a
				630	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]	631	CVS base</a>. Check the <a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	632	href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
				633	page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	634	</li>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	635	<li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	636	</ul>
				637
				638	<h2><a name="News">News</a></h2>
				639
Daniel Veillard	944b5ff	1999-12-15 19:08:24 +0000	[diff] [blame]	640	<h3>CVS only : check the <a
				641	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]	642	for a really accurate description</h3>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	643
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	644	<p>Items not finished and worked on, get in touch with the list if you want
				645	to test those</p>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	646	<ul>
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	647	<li>More testing on RelaxNG</li>
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	648	<li>Finishing up <a href="http://www.w3.org/TR/xmlschema-1/">XML
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	649	Schemas</a></li>
				650	</ul>
				651
Daniel Veillard	92fc02c	2003-04-24 23:12:35 +0000	[diff] [blame]	652	<h3>2.5.7: Apr 25 2003</h3>
				653	<ul>
				654	<li>Relax-NG: Compiling to regexp and streaming validation on top of the
				655	xmlReader interface, added to xmllint --stream</li>
				656	<li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li>
				657	<li>Support for large files: RGN validated a 4.5GB instance</li>
				658	<li>Thread support is now configured in by default</li>
				659	<li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes
				660	(Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser
				661	and zero bytes handling, some missing Windows file path conversions,
				662	behaviour of the parser and validator in the presence of "out of memory"
Daniel Veillard	93d9525	2003-04-29 20:25:40 +0000	[diff] [blame]	663	error conditions</li>
Daniel Veillard	92fc02c	2003-04-24 23:12:35 +0000	[diff] [blame]	664	<li>extended the API to be able to plug a garbage collecting memory
				665	allocator, added xmlMallocAtomic() and modified the allocations
				666	accordingly.</li>
				667	<li>Performances: removed excessive malloc() calls, speedup of the push and
				668	xmlReader interfaces, removed excessive thread locking</li>
				669	<li>Documentation: man page (John Fleck), xmlReader documentation</li>
				670	<li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li>
				671	</ul>
				672
Daniel Veillard	c2d4a93	2003-04-01 11:13:05 +0000	[diff] [blame]	673	<h3>2.5.6: Apr 1 2003</h3>
				674	<ul>
				675	<li>Fixed W3C XML Schemas datatype, should be compliant now except for
				676	binHex and base64 which are not supported yet.</li>
				677	<li>bug fixes: non-ASCII IDs, HTML output, XInclude on large docs and
				678	XInclude entities handling, encoding detection on external subsets, XML
				679	Schemas bugs and memory leaks, HTML parser (James Bursa)</li>
				680	<li>portability: python/trio (Albert Chin), Sun compiler warnings</li>
				681	<li>documentation: added --relaxng option to xmllint man page (John)</li>
				682	<li>improved error reporting: xml:space, start/end tag mismatches, Relax NG
				683	errors</li>
				684	</ul>
				685
				686	<h3>2.5.5: Mar 24 2003</h3>
Daniel Veillard	d8da01c	2003-03-24 15:58:23 +0000	[diff] [blame]	687	<ul>
				688	<li>Lot of fixes on the Relax NG implementation. More testing including
				689	DocBook and TEI examples.</li>
				690	<li>Increased the support for W3C XML Schemas datatype</li>
				691	<li>Several bug fixes in the URI handling layer</li>
				692	<li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding
				693	conversion, line counting in the parser.</li>
				694	<li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li>
				695	<li>Fixed the RPM spec file name</li>
				696	</ul>
				697
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	698	<h3>2.5.4: Feb 20 2003</h3>
				699	<ul>
				700	<li>Conformance testing and lot of fixes on Relax NG and XInclude
				701	implementation</li>
				702	<li>Implementation of XPointer element() scheme</li>
				703	<li>Bug fixes: XML parser, XInclude entities merge, validity checking on
				704	namespaces,
				705	<p>2 serialization bugs, node info generation problems, a DTD regexp
				706	generation problem.</p>
				707	</li>
				708	<li>Portability: windows updates and path canonicalization (Igor)</li>
				709	<li>A few typo fixes (Kjartan Maraas)</li>
				710	<li>Python bindings generator fixes (Stephane Bidoul)</li>
				711	</ul>
				712
Daniel Veillard	1d788d2	2003-02-10 16:21:58 +0000	[diff] [blame]	713	<h3>2.5.3: Feb 10 2003</h3>
				714	<ul>
				715	<li>RelaxNG and XML Schemas datatypes improvements, and added a first
				716	version of RelaxNG Python bindings</li>
				717	<li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for
				718	serializing namespace nodes, encoding conversion bug, XHTML1
				719	serialization</li>
				720	<li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li>
				721	</ul>
				722
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	723	<h3>2.5.2: Feb 5 2003</h3>
				724	<ul>
				725	<li>First implementation of RelaxNG, added --relaxng flag to xmllint</li>
				726	<li>Schemas support now compiled in by default.</li>
				727	<li>Bug fixes: DTD validation, namespace checking, XInclude and entities,
				728	delegateURI in XML Catalogs, HTML parser, XML reader (Stéphane Bidoul),
				729	XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory
				730	consumption, HTML parser, HTML serialization in the presence of
				731	namespaces</li>
				732	<li>added an HTML API to check elements and attributes.</li>
				733	<li>Documentation improvement, PDF for the tutorial (John Fleck), doc
				734	patches (Stefan Kost)</li>
				735	<li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li>
				736	<li>Added python bindings for XPointer, contextual error reporting
				737	(Stéphane Bidoul)</li>
				738	<li>URI/file escaping problems (Stefano Zacchiroli)</li>
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	739	</ul>
				740
Daniel Veillard	e2830f1	2003-01-08 17:47:49 +0000	[diff] [blame]	741	<h3>2.5.1: Jan 8 2003</h3>
				742	<ul>
				743	<li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li>
				744	<li>documentation updates (John)</li>
				745	<li>a couple of XmlTextReader fixes</li>
				746	</ul>
				747
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	748	<h3>2.5.0: Jan 6 2003</h3>
				749	<ul>
				750	<li>New <a href="xmlreader.html">XmltextReader interface</a> based on C#
				751	API (with help of Stéphane Bidoul)</li>
				752	<li>Windows: more exports, including the new API (Igor)</li>
				753	<li>XInclude fallback fix</li>
				754	<li>Python: bindings for the new API, packaging (Stéphane Bidoul),
				755	drv_libxml2.py Python xml.sax driver (Stéphane Bidoul), fixes, speedup
				756	and iterators for Python-2.2 (Hannu Krosing)</li>
				757	<li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update
				758	(John)</li>
				759	<li>Fix an XML parser bug raised by Vyacheslav Pindyura</li>
				760	<li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li>
				761	<li>Entities handling fixes</li>
				762	<li>new API to optionally track node creation and deletion (Lukas
				763	Schroeder)</li>
				764	<li>Added documentation for the XmltextReader interface and some <a
				765	href="guidelines.html">XML guidelines</a></li>
				766	</ul>
				767
Daniel Veillard	c1eed32	2002-12-12 11:01:32 +0000	[diff] [blame]	768	<h3>2.4.30: Dec 12 2002</h3>
				769	<ul>
				770	<li>2.4.29 broke the python bindings, rereleasing</li>
				771	<li>Improvement/fixes of the XML API generator, and couple of minor code
				772	fixes.</li>
				773	</ul>
				774
Daniel Veillard	9b4bb4d	2002-12-11 19:28:47 +0000	[diff] [blame]	775	<h3>2.4.29: Dec 11 2002</h3>
				776	<ul>
				777	<li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings
				778	(Stéphane Bidoul), Mingw (Magnus Henoch), and export list updates</li>
				779	<li>Fix for prev in python bindings (ERDI Gergo)</li>
				780	<li>Fix for entities handling (Marcus Clarke)</li>
				781	<li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1
				782	dump</li>
				783	<li>Fix for URI parsing when handling URNs with fragment identifiers</li>
				784	<li>Fix for HTTP URL escaping problem</li>
				785	<li>added an TextXmlReader (C#) like API (work in progress)</li>
				786	<li>Rewrote the API in XML generation script, includes a C parser and saves
				787	more informations needed for C# bindings</li>
				788	</ul>
				789
Daniel Veillard	f9c4cad	2002-11-22 15:57:07 +0000	[diff] [blame]	790	<h3>2.4.28: Nov 22 2002</h3>
				791	<ul>
				792	<li>a couple of python binding fixes</li>
				793	<li>2 bug fixes in the XML push parser</li>
				794	<li>potential memory leak removed (Martin Stoilov)</li>
				795	<li>fix to the configure script for Unix (Dimitri Papadopoulos)</li>
				796	<li>added encoding support for XInclude parse="text"</li>
				797	<li>autodetection of XHTML1 and specific serialization rules added</li>
Daniel Veillard	9b4bb4d	2002-12-11 19:28:47 +0000	[diff] [blame]	798	<li>nasty threading bug fixed (William Brack)</li>
Daniel Veillard	f9c4cad	2002-11-22 15:57:07 +0000	[diff] [blame]	799	</ul>
				800
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	801	<h3>2.4.27: Nov 17 2002</h3>
				802	<ul>
				803	<li>fixes for the Python bindings</li>
				804	<li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(),
				805	HTML parser, Schemas (Charles Bozeman), document fragment support
				806	(Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer,
				807	xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr
				808	Pajas), entities processing</li>
				809	<li>added grep to xmllint --shell</li>
				810	<li>VMS update patch from Craig A. Berry</li>
				811	<li>cleanup of the Windows build with support for more compilers (Igor),
				812	better thread support on Windows</li>
				813	<li>cleanup of Unix Makefiles and spec file</li>
				814	<li>Improvements to the documentation (John Fleck)</li>
				815	</ul>
				816
Daniel Veillard	4826743	2002-10-18 11:21:38 +0000	[diff] [blame]	817	<h3>2.4.26: Oct 18 2002</h3>
				818	<ul>
				819	<li>Patches for Windows CE port, improvements on Windows paths handling</li>
				820	<li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() ,
				821	HTML serialization, Namespace compliance, and a number of small
				822	problems</li>
				823	</ul>
				824
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	825	<h3>2.4.25: Sep 26 2002</h3>
				826	<ul>
				827	<li>A number of bug fixes: XPath, validation, Python bindings, DOM and
				828	tree, xmlI/O, Html</li>
				829	<li>Serious rewrite of XInclude</li>
				830	<li>Made XML Schemas regexp part of the default build and APIs, small fix
				831	and improvement of the regexp core</li>
				832	<li>Changed the validation code to reuse XML Schemas regexp APIs</li>
				833	<li>Better handling of Windows file paths, improvement of Makefiles (Igor,
				834	Daniel Gehriger, Mark Vakoc)</li>
				835	<li>Improved the python I/O bindings, the tests, added resolver and regexp
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	836	APIs</li>
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	837	<li>New logos from Marc Liyanage</li>
				838	<li>Tutorial improvements: John Fleck, Christopher Harris</li>
				839	<li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe
				840	Merlet)</li>
				841	<li>removal of all stderr/perror use for error reporting</li>
				842	<li>Better error reporting: XPath and DTD validation</li>
				843	<li>update of the trio portability layer (Bjorn Reese)</li>
				844	</ul>
				845
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	846	<p><strong>2.4.24: Aug 22 2002</strong></p>
				847	<ul>
				848	<li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li>
				849	<li>Python binding fixes: makefiles (William), generator, rpm build, x86-64
				850	(fcrozat)</li>
				851	<li>HTML <style> and boolean attributes serializer fixes</li>
				852	<li>C14N improvements by Aleksey</li>
Daniel Veillard	e166254	2002-08-28 11:50:59 +0000	[diff] [blame]	853	<li>doc cleanups: Rick Jones</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	854	<li>Windows compiler makefile updates: Igor and Elizabeth Barham</li>
				855	<li>XInclude: implementation of fallback and xml:base fixup added</li>
				856	</ul>
				857
Daniel Veillard	782afda	2002-07-08 15:12:49 +0000	[diff] [blame]	858	<h3>2.4.23: July 6 2002</h3>
				859	<ul>
				860	<li>performances patches: Peter Jacobi</li>
				861	<li>c14n fixes, testsuite and performances: Aleksey Sanin</li>
				862	<li>added xmlDocFormatDump: Chema Celorio</li>
				863	<li>new tutorial: John Fleck</li>
				864	<li>new hash functions and performances: Sander Vesik, portability fix from
				865	Peter Jacobi</li>
				866	<li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and
				867	HTML parsers, ID lookup function</li>
				868	<li>removal of all remaining sprintf: Aleksey Sanin</li>
				869	</ul>
				870
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	871	<h3>2.4.22: May 27 2002</h3>
				872	<ul>
				873	<li>a number of bug fixes: configure scripts, base handling, parser, memory
				874	usage, HTML parser, XPath, documentation (Christian Cornelssen),
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	875	indentation, URI parsing</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	876	<li>Optimizations for XMLSec, fixing and making public some of the network
				877	protocol handlers (Aleksey)</li>
				878	<li>performance patch from Gary Pennington</li>
				879	<li>Charles Bozeman provided date and time support for XML Schemas
				880	datatypes</li>
				881	</ul>
				882
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	883	<h3>2.4.21: Apr 29 2002</h3>
				884
				885	<p>This release is both a bug fix release and also contains the early XML
				886	Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a
				887	href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all
				888	interfaces are likely to change, there is huge holes, it is clearly a work in
				889	progress and don't even think of putting this code in a production system,
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	890	it's actually not compiled in by default. The real fixes are:</p>
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	891	<ul>
				892	<li>a couple of bugs or limitations introduced in 2.4.20</li>
				893	<li>patches for Borland C++ and MSC by Igor</li>
				894	<li>some fixes on XPath strings and conformance patches by Richard
				895	Jinks</li>
				896	<li>patch from Aleksey for the ExcC14N specification</li>
				897	<li>OSF/1 bug fix by Bjorn</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	898	</ul>
				899
Daniel Veillard	a7084cd	2002-04-15 17:12:47 +0000	[diff] [blame]	900	<h3>2.4.20: Apr 15 2002</h3>
				901	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	902	<li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li>
Daniel Veillard	a7084cd	2002-04-15 17:12:47 +0000	[diff] [blame]	903	<li>XPath conformance testing by Richard Jinks</li>
				904	<li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings,
				905	libxml.m4</li>
				906	</ul>
				907
Daniel Veillard	1927409	2002-03-25 16:48:03 +0000	[diff] [blame]	908	<h3>2.4.19: Mar 25 2002</h3>
				909	<ul>
				910	<li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8
				911	encoder</li>
				912	<li>portability fixes in the HTTP code</li>
Daniel Veillard	b2fb8ed	2002-04-01 09:33:12 +0000	[diff] [blame]	913	<li>memory allocation checks using valgrind, and profiling tests</li>
Daniel Veillard	1927409	2002-03-25 16:48:03 +0000	[diff] [blame]	914	<li>revamp of the Windows build and Makefiles</li>
				915	</ul>
				916
Daniel Veillard	34ce8be	2002-03-18 19:37:11 +0000	[diff] [blame]	917	<h3>2.4.18: Mar 18 2002</h3>
				918	<ul>
				919	<li>bug fixes: tree, SAX, canonicalization, validation, portability,
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	920	XPath</li>
Daniel Veillard	34ce8be	2002-03-18 19:37:11 +0000	[diff] [blame]	921	<li>removed the --with-buffer option it was becoming unmaintainable</li>
				922	<li>serious cleanup of the Python makefiles</li>
				923	<li>speedup patch to XPath very effective for DocBook stylesheets</li>
				924	<li>Fixes for Windows build, cleanup of the documentation</li>
				925	</ul>
				926
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	927	<h3>2.4.17: Mar 8 2002</h3>
				928	<ul>
				929	<li>a lot of bug fixes, including "namespace nodes have no parents in
				930	XPath"</li>
				931	<li>fixed/improved the Python wrappers, added more examples and more
				932	regression tests, XPath extension functions can now return node-sets</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	933	<li>added the XML Canonicalization support from Aleksey Sanin</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	934	</ul>
				935
Daniel Veillard	5f4b599	2002-02-20 10:22:49 +0000	[diff] [blame]	936	<h3>2.4.16: Feb 20 2002</h3>
				937	<ul>
				938	<li>a lot of bug fixes, most of them were triggered by the XML Testsuite
				939	from OASIS and W3C. Compliance has been significantly improved.</li>
				940	<li>a couple of portability fixes too.</li>
				941	</ul>
				942
Daniel Veillard	397ff11	2002-02-11 18:27:20 +0000	[diff] [blame]	943	<h3>2.4.15: Feb 11 2002</h3>
				944	<ul>
				945	<li>Fixed the Makefiles, especially the python module ones</li>
				946	<li>A few bug fixes and cleanup</li>
				947	<li>Includes cleanup</li>
				948	</ul>
				949
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	950	<h3>2.4.14: Feb 8 2002</h3>
				951	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	952	<li>Change of License to the <a
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	953	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	954	License</a> basically for integration in XFree86 codebase, and removing
				955	confusion around the previous dual-licensing</li>
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	956	<li>added Python bindings, beta software but should already be quite
				957	complete</li>
				958	<li>a large number of fixes and cleanups, especially for all tree
				959	manipulations</li>
				960	<li>cleanup of the headers, generation of a reference API definition in
				961	XML</li>
				962	</ul>
				963
				964	<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard	744683d	2002-01-14 17:30:20 +0000	[diff] [blame]	965	<ul>
				966	<li>update of the documentation: John Fleck and Charlie Bozeman</li>
				967	<li>cleanup of timing code from Justin Fletcher</li>
				968	<li>fixes for Windows and initial thread support on Win32: Igor and Serguei
				969	Narojnyi</li>
				970	<li>Cygwin patch from Robert Collins</li>
				971	<li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
				972	</ul>
				973
Daniel Veillard	ef90ba7	2001-12-07 14:24:22 +0000	[diff] [blame]	974	<h3>2.4.12: Dec 7 2001</h3>
				975	<ul>
				976	<li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
				977	XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
				978	(robert)</li>
				979	<li>Eric Lavigne contributed project files for MacOS</li>
				980	<li>some makefiles cleanups</li>
				981	</ul>
				982
Daniel Veillard	a487105	2001-11-26 13:19:48 +0000	[diff] [blame]	983	<h3>2.4.11: Nov 26 2001</h3>
				984	<ul>
				985	<li>fixed a couple of errors in the includes, fixed a few bugs, some code
				986	cleanups</li>
				987	<li>xmllint man pages improvement by Heiko Rupp</li>
				988	<li>updated VMS build instructions from John A Fotheringham</li>
				989	<li>Windows Makefiles updates from Igor</li>
				990	</ul>
				991
Daniel Veillard	43d3f61	2001-11-10 11:57:23 +0000	[diff] [blame]	992	<h3>2.4.10: Nov 10 2001</h3>
				993	<ul>
				994	<li>URI escaping fix (Joel Young)</li>
				995	<li>added xmlGetNodePath() (for paths or XPointers generation)</li>
				996	<li>Fixes namespace handling problems when using DTD and validation</li>
				997	<li>improvements on xmllint: Morus Walter patches for --format and
				998	--encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
				999	<li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
				1000	<li>fixes to the HTML parser</li>
				1001	</ul>
				1002
				1003	<h3>2.4.9: Nov 6 2001</h3>
				1004	<ul>
				1005	<li>fixes more catalog bugs</li>
				1006	<li>avoid a compilation problem, improve xmlGetLineNo()</li>
				1007	</ul>
				1008
Daniel Veillard	ed421aa	2001-11-04 21:22:45 +0000	[diff] [blame]	1009	<h3>2.4.8: Nov 4 2001</h3>
				1010	<ul>
				1011	<li>fixed SGML catalogs broken in previous release, updated xmlcatalog
				1012	tool</li>
				1013	<li>fixed a compile errors and some includes troubles.</li>
				1014	</ul>
				1015
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	1016	<h3>2.4.7: Oct 30 2001</h3>
				1017	<ul>
				1018	<li>exported some debugging interfaces</li>
				1019	<li>serious rewrite of the catalog code</li>
				1020	<li>integrated Gary Pennington thread safety patch, added configure option
				1021	and regression tests</li>
				1022	<li>removed an HTML parser bug</li>
				1023	<li>fixed a couple of potentially serious validation bugs</li>
				1024	<li>integrated the SGML DocBook support in xmllint</li>
				1025	<li>changed the nanoftp anonymous login passwd</li>
				1026	<li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
				1027	<li>general bug fixes</li>
				1028	<li>updated xmllint man page by John Fleck</li>
				1029	<li>some VMS and Windows updates</li>
				1030	</ul>
				1031
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	1032	<h3>2.4.6: Oct 10 2001</h3>
				1033	<ul>
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	1034	<li>added an updated man pages by John Fleck</li>
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	1035	<li>portability and configure fixes</li>
				1036	<li>an infinite loop on the HTML parser was removed (William)</li>
				1037	<li>Windows makefile patches from Igor</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1038	<li>fixed half a dozen bugs reported for libxml or libxslt</li>
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	1039	<li>updated xmlcatalog to be able to modify SGML super catalogs</li>
				1040	</ul>
				1041
Daniel Veillard	dadd087	2001-09-15 09:21:44 +0000	[diff] [blame]	1042	<h3>2.4.5: Sep 14 2001</h3>
				1043	<ul>
				1044	<li>Remove a few annoying bugs in 2.4.4</li>
				1045	<li>forces the HTML serializer to output decimal charrefs since some
				1046	version of Netscape can't handle hexadecimal ones</li>
				1047	</ul>
				1048
				1049	<h3>1.8.16: Sep 14 2001</h3>
				1050	<ul>
				1051	<li>maintenance release of the old libxml1 branch, couple of bug and
				1052	portability fixes</li>
				1053	</ul>
				1054
Daniel Veillard	04382ae	2001-09-12 18:51:30 +0000	[diff] [blame]	1055	<h3>2.4.4: Sep 12 2001</h3>
				1056	<ul>
				1057	<li>added --convert to xmlcatalog, bug fixes and cleanups of XML
				1058	Catalog</li>
				1059	<li>a few bug fixes and some portability changes</li>
				1060	<li>some documentation cleanups</li>
				1061	</ul>
				1062
Daniel Veillard	3993690	2001-08-24 00:49:01 +0000	[diff] [blame]	1063	<h3>2.4.3: Aug 23 2001</h3>
				1064	<ul>
				1065	<li>XML Catalog support see the doc</li>
				1066	<li>New NaN/Infinity floating point code</li>
				1067	<li>A few bug fixes</li>
				1068	</ul>
				1069
				1070	<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1071	<ul>
				1072	<li>adds xmlLineNumbersDefault() to control line number generation</li>
				1073	<li>lot of bug fixes</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1074	<li>the Microsoft MSC projects files should now be up to date</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1075	<li>inheritance of namespaces from DTD defaulted attributes</li>
				1076	<li>fixes a serious potential security bug</li>
				1077	<li>added a --format option to xmllint</li>
				1078	</ul>
				1079
				1080	<h3>2.4.1: July 24 2001</h3>
				1081	<ul>
				1082	<li>possibility to keep line numbers in the tree</li>
				1083	<li>some computation NaN fixes</li>
				1084	<li>extension of the XPath API</li>
				1085	<li>cleanup for alpha and ia64 targets</li>
				1086	<li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard	09ab7e1	2001-07-10 15:49:44 +0000	[diff] [blame]	1087	</ul>
				1088
				1089	<h3>2.4.0: July 10 2001</h3>
				1090	<ul>
				1091	<li>Fixed a few bugs in XPath, validation, and tree handling.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1092	<li>Fixed XML Base implementation, added a couple of examples to the
Daniel Veillard	09ab7e1	2001-07-10 15:49:44 +0000	[diff] [blame]	1093	regression tests</li>
				1094	<li>A bit of cleanup</li>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1095	</ul>
				1096
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1097	<h3>2.3.14: July 5 2001</h3>
				1098	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1099	<li>fixed some entities problems and reduce memory requirement when
				1100	substituting them</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1101	<li>lots of improvements in the XPath queries interpreter can be
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1102	substantially faster</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1103	<li>Makefiles and configure cleanups</li>
				1104	<li>Fixes to XPath variable eval, and compare on empty node set</li>
				1105	<li>HTML tag closing bug fixed</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1106	<li>Fixed an URI reference computation problem when validating</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1107	</ul>
				1108
Daniel Veillard	2adbb51	2001-06-28 16:20:36 +0000	[diff] [blame]	1109	<h3>2.3.13: June 28 2001</h3>
				1110	<ul>
				1111	<li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
				1112	<li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
				1113	</ul>
				1114
				1115	<h3>1.8.14: June 28 2001</h3>
				1116	<ul>
				1117	<li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
				1118	<li>Small Makefile fix</li>
				1119	</ul>
				1120
Daniel Veillard	1164810	2001-06-26 16:08:24 +0000	[diff] [blame]	1121	<h3>2.3.12: June 26 2001</h3>
				1122	<ul>
				1123	<li>lots of cleanup</li>
				1124	<li>a couple of validation fix</li>
				1125	<li>fixed line number counting</li>
				1126	<li>fixed serious problems in the XInclude processing</li>
				1127	<li>added support for UTF8 BOM at beginning of entities</li>
				1128	<li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
				1129	miscompile uri.c (William), Thomas Leitner provided a fix for the
				1130	optimizer on Tru64</li>
				1131	<li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
				1132	compilation on Windows MSC</li>
				1133	<li>update of libxml-doc.el (Felix Natter)</li>
				1134	<li>fixed 2 bugs in URI normalization code</li>
				1135	</ul>
				1136
Daniel Veillard	e3c81b5	2001-06-17 14:50:34 +0000	[diff] [blame]	1137	<h3>2.3.11: June 17 2001</h3>
				1138	<ul>
				1139	<li>updates to trio, Makefiles and configure should fix some portability
				1140	problems (alpha)</li>
				1141	<li>fixed some HTML serialization problems (pre, script, and block/inline
				1142	handling), added encoding aware APIs, cleanup of this code</li>
				1143	<li>added xmlHasNsProp()</li>
				1144	<li>implemented a specific PI for encoding support in the DocBook SGML
				1145	parser</li>
				1146	<li>some XPath fixes (-Infinity, / as a function parameter and namespaces
				1147	node selection)</li>
				1148	<li>fixed a performance problem and an error in the validation code</li>
				1149	<li>fixed XInclude routine to implement the recursive behaviour</li>
				1150	<li>fixed xmlFreeNode problem when libxml is included statically twice</li>
				1151	<li>added --version to xmllint for bug reports</li>
				1152	</ul>
				1153
Daniel Veillard	2e4f188	2001-06-01 10:11:57 +0000	[diff] [blame]	1154	<h3>2.3.10: June 1 2001</h3>
				1155	<ul>
				1156	<li>fixed the SGML catalog support</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1157	<li>a number of reported bugs got fixed, in XPath, iconv detection,
				1158	XInclude processing</li>
Daniel Veillard	2e4f188	2001-06-01 10:11:57 +0000	[diff] [blame]	1159	<li>XPath string function should now handle unicode correctly</li>
				1160	</ul>
				1161
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1162	<h3>2.3.9: May 19 2001</h3>
				1163
				1164	<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
				1165	<ul>
				1166	<li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1167	<li>some serious speed optimization again</li>
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1168	<li>some documentation cleanups</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1169	<li>trying to get better linking on Solaris (-R)</li>
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1170	<li>XPath API cleanup from Thomas Broyer</li>
				1171	<li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
				1172	xmlValidGetValidElements()</li>
				1173	<li>Added an INSTALL file</li>
				1174	<li>Attribute removal added to API: #54433</li>
				1175	<li>added a basic support for SGML catalogs</li>
				1176	<li>fixed xmlKeepBlanksDefault(0) API</li>
				1177	<li>bugfix in xmlNodeGetLang()</li>
				1178	<li>fixed a small configure portability problem</li>
				1179	<li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
				1180	</ul>
				1181
Daniel Veillard	a265af7	2001-05-14 11:13:58 +0000	[diff] [blame]	1182	<h3>1.8.13: May 14 2001</h3>
				1183	<ul>
				1184	<li>bugfixes release of the old libxml1 branch used by Gnome</li>
				1185	</ul>
				1186
Daniel Veillard	3bbbe6f	2001-05-03 11:15:37 +0000	[diff] [blame]	1187	<h3>2.3.8: May 3 2001</h3>
				1188	<ul>
				1189	<li>Integrated an SGML DocBook parser for the Gnome project</li>
				1190	<li>Fixed a few things in the HTML parser</li>
				1191	<li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
				1192	point portability issue</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1193	<li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
				1194	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]	1195	<li>incorporated more Windows cleanup</li>
				1196	<li>added xmlSaveFormatFile()</li>
				1197	<li>fixed problems in copying nodes with entities references (gdome)</li>
				1198	<li>removed some troubles surrounding the new validation module</li>
				1199	</ul>
				1200
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1201	<h3>2.3.7: April 22 2001</h3>
				1202	<ul>
				1203	<li>lots of small bug fixes, corrected XPointer</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1204	<li>Non deterministic content model validation support</li>
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1205	<li>added xmlDocCopyNode for gdome2</li>
				1206	<li>revamped the way the HTML parser handles end of tags</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1207	<li>XPath: corrections of namespaces support and number formatting</li>
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1208	<li>Windows: Igor Zlatkovic patches for MSC compilation</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1209	<li>HTML output fixes from P C Chow and William M. Brack</li>
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1210	<li>Improved validation speed sensible for DocBook</li>
				1211	<li>fixed a big bug with ID declared in external parsed entities</li>
				1212	<li>portability fixes, update of Trio from Bjorn Reese</li>
				1213	</ul>
				1214
Daniel Veillard	afc7311	2001-04-11 11:51:41 +0000	[diff] [blame]	1215	<h3>2.3.6: April 8 2001</h3>
				1216	<ul>
				1217	<li>Code cleanup using extreme gcc compiler warning options, found and
				1218	cleared half a dozen potential problem</li>
				1219	<li>the Eazel team found an XML parser bug</li>
				1220	<li>cleaned up the user of some of the string formatting function. used the
				1221	trio library code to provide the one needed when the platform is missing
				1222	them</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1223	<li>xpath: removed a memory leak and fixed the predicate evaluation
				1224	problem, extended the testsuite and cleaned up the result. XPointer seems
				1225	broken ...</li>
Daniel Veillard	afc7311	2001-04-11 11:51:41 +0000	[diff] [blame]	1226	</ul>
				1227
Daniel Veillard	56a4cb8	2001-03-24 17:00:36 +0000	[diff] [blame]	1228	<h3>2.3.5: Mar 23 2001</h3>
				1229	<ul>
				1230	<li>Biggest change is separate parsing and evaluation of XPath expressions,
				1231	there is some new APIs for this too</li>
				1232	<li>included a number of bug fixes(XML push parser, 51876, notations,
				1233	52299)</li>
				1234	<li>Fixed some portability issues</li>
				1235	</ul>
				1236
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1237	<h3>2.3.4: Mar 10 2001</h3>
				1238	<ul>
				1239	<li>Fixed bugs #51860 and #51861</li>
				1240	<li>Added a global variable xmlDefaultBufferSize to allow default buffer
				1241	size to be application tunable.</li>
				1242	<li>Some cleanup in the validation code, still a bug left and this part
				1243	should probably be rewritten to support ambiguous content model :-\</li>
				1244	<li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
				1245	parser</li>
				1246	<li>Fixed another bug in xmlNodeGetContent()</li>
				1247	<li>Bjorn fixed XPath node collection and Number formatting</li>
				1248	<li>Fixed a loop reported in the HTML parsing</li>
				1249	<li>blank space are reported even if the Dtd content model proves that they
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1250	are formatting spaces, this is for XML conformance</li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1251	</ul>
				1252
Daniel Veillard	b402c07	2001-03-01 17:28:58 +0000	[diff] [blame]	1253	<h3>2.3.3: Mar 1 2001</h3>
				1254	<ul>
				1255	<li>small change in XPath for XSLT</li>
				1256	<li>documentation cleanups</li>
				1257	<li>fix in validation by Gary Pennington</li>
				1258	<li>serious parsing performances improvements</li>
				1259	</ul>
				1260
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1261	<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard	7168110	2001-02-24 17:48:53 +0000	[diff] [blame]	1262	<ul>
				1263	<li>chasing XPath bugs, found a bunch, completed some TODO</li>
				1264	<li>fixed a Dtd parsing bug</li>
				1265	<li>fixed a bug in xmlNodeGetContent</li>
				1266	<li>ID/IDREF support partly rewritten by Gary Pennington</li>
				1267	</ul>
				1268
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1269	<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1270	<ul>
				1271	<li>some XPath and HTML bug fixes for XSLT</li>
				1272	<li>small extension of the hash table interfaces for DOM gdome2
				1273	implementation</li>
				1274	<li>A few bug fixes</li>
				1275	</ul>
				1276
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1277	<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]	1278	<ul>
				1279	<li>Lots of XPath bug fixes</li>
				1280	<li>Add a mode with Dtd lookup but without validation error reporting for
				1281	XSLT</li>
				1282	<li>Add support for text node without escaping (XSLT)</li>
				1283	<li>bug fixes for xmlCheckFilename</li>
				1284	<li>validation code bug fixes from Gary Pennington</li>
				1285	<li>Patch from Paul D. Smith correcting URI path normalization</li>
				1286	<li>Patch to allow simultaneous install of libxml-devel and
				1287	libxml2-devel</li>
				1288	<li>the example Makefile is now fixed</li>
				1289	<li>added HTML to the RPM packages</li>
				1290	<li>tree copying bugfixes</li>
				1291	<li>updates to Windows makefiles</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1292	<li>optimization patch from Bjorn Reese</li>
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1293	</ul>
				1294
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1295	<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard	503b893	2001-01-05 06:36:31 +0000	[diff] [blame]	1296	<ul>
				1297	<li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
				1298	<li>added htmlHandleOmittedElem()</li>
				1299	<li>Applied Bjorn Reese's IPV6 first patch</li>
				1300	<li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1301	<li>added XPointer xmlns() new scheme support</li>
Daniel Veillard	503b893	2001-01-05 06:36:31 +0000	[diff] [blame]	1302	</ul>
				1303
Daniel Veillard	2ddd23d	2000-11-25 10:42:19 +0000	[diff] [blame]	1304	<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard	9d343c4	2000-11-25 10:12:43 +0000	[diff] [blame]	1305	<ul>
				1306	<li>Fix the Windows problems of 2.2.8</li>
				1307	<li>integrate OpenVMS patches</li>
				1308	<li>better handling of some nasty HTML input</li>
				1309	<li>Improved the XPointer implementation</li>
				1310	<li>integrate a number of provided patches</li>
				1311	</ul>
				1312
Daniel Veillard	2ddd23d	2000-11-25 10:42:19 +0000	[diff] [blame]	1313	<h3>2.2.9: Nov 25 2000</h3>
				1314	<ul>
				1315	<li>erroneous release :-(</li>
				1316	</ul>
				1317
Daniel Veillard	28929b2	2000-11-13 18:22:49 +0000	[diff] [blame]	1318	<h3>2.2.8: Nov 13 2000</h3>
				1319	<ul>
				1320	<li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
				1321	support</li>
				1322	<li>Patch in conditional section handling</li>
				1323	<li>updated MS compiler project</li>
				1324	<li>fixed some XPath problems</li>
				1325	<li>added an URI escaping function</li>
				1326	<li>some other bug fixes</li>
				1327	</ul>
				1328
				1329	<h3>2.2.7: Oct 31 2000</h3>
				1330	<ul>
				1331	<li>added message redirection</li>
				1332	<li>XPath improvements (thanks TOM !)</li>
				1333	<li>xmlIOParseDTD() added</li>
				1334	<li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
				1335	<li>some cleanup of the Makefile, autoconf and the distribution content</li>
				1336	</ul>
				1337
Daniel Veillard	29a11cc	2000-10-25 13:32:39 +0000	[diff] [blame]	1338	<h3>2.2.6: Oct 25 2000:</h3>
				1339	<ul>
				1340	<li>Added an hash table module, migrated a number of internal structure to
				1341	those</li>
				1342	<li>Fixed a posteriori validation problems</li>
				1343	<li>HTTP module cleanups</li>
				1344	<li>HTML parser improvements (tag errors, script/style handling, attribute
				1345	normalization)</li>
				1346	<li>coalescing of adjacent text nodes</li>
				1347	<li>couple of XPath bug fixes, exported the internal API</li>
				1348	</ul>
				1349
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1350	<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	1351	<ul>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1352	<li>XPointer implementation and testsuite</li>
				1353	<li>Lot of XPath fixes, added variable and functions registration, more
				1354	tests</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1355	<li>Portability fixes, lots of enhancements toward an easy Windows build
				1356	and release</li>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1357	<li>Late validation fixes</li>
				1358	<li>Integrated a lot of contributed patches</li>
				1359	<li>added memory management docs</li>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1360	<li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1361	</ul>
				1362
				1363	<h3>2.2.4: Oct 1 2000:</h3>
				1364	<ul>
				1365	<li>main XPath problem fixed</li>
				1366	<li>Integrated portability patches for Windows</li>
				1367	<li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1368	</ul>
				1369
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1370	<h3>2.2.3: Sep 17 2000</h3>
				1371	<ul>
				1372	<li>bug fixes</li>
				1373	<li>cleanup of entity handling code</li>
				1374	<li>overall review of all loops in the parsers, all sprintf usage has been
				1375	checked too</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1376	<li>Far better handling of larges Dtd. Validating against DocBook XML Dtd
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1377	works smoothly now.</li>
				1378	</ul>
				1379
				1380	<h3>1.8.10: Sep 6 2000</h3>
				1381	<ul>
				1382	<li>bug fix release for some Gnome projects</li>
				1383	</ul>
				1384
				1385	<h3>2.2.2: August 12 2000</h3>
Daniel Veillard	786d7c8	2000-08-12 23:38:57 +0000	[diff] [blame]	1386	<ul>
				1387	<li>mostly bug fixes</li>
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	1388	<li>started adding routines to access xml parser context options</li>
Daniel Veillard	786d7c8	2000-08-12 23:38:57 +0000	[diff] [blame]	1389	</ul>
				1390
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1391	<h3>2.2.1: July 21 2000</h3>
Daniel Veillard	a2679fa	2000-07-22 02:38:15 +0000	[diff] [blame]	1392	<ul>
				1393	<li>a purely bug fixes release</li>
				1394	<li>fixed an encoding support problem when parsing from a memory block</li>
				1395	<li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1396	<li>removed a bug in the function allowing to override the memory
				1397	allocation routines</li>
Daniel Veillard	a2679fa	2000-07-22 02:38:15 +0000	[diff] [blame]	1398	</ul>
				1399
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1400	<h3>2.2.0: July 14 2000</h3>
Daniel Veillard	94e9060	2000-07-17 14:38:19 +0000	[diff] [blame]	1401	<ul>
				1402	<li>applied a lot of portability fixes</li>
				1403	<li>better encoding support/cleanup and saving (content is now always
				1404	encoded in UTF-8)</li>
				1405	<li>the HTML parser now correctly handles encodings</li>
				1406	<li>added xmlHasProp()</li>
				1407	<li>fixed a serious problem with &#38;</li>
				1408	<li>propagated the fix to FTP client</li>
				1409	<li>cleanup, bugfixes, etc ...</li>
				1410	<li>Added a page about <a href="encoding.html">libxml Internationalization
				1411	support</a></li>
				1412	</ul>
				1413
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1414	<h3>1.8.9: July 9 2000</h3>
				1415	<ul>
				1416	<li>fixed the spec the RPMs should be better</li>
				1417	<li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
				1418	rpmfind users problem</li>
				1419	</ul>
				1420
Daniel Veillard	6388e17	2000-07-03 16:07:19 +0000	[diff] [blame]	1421	<h3>2.1.1: July 1 2000</h3>
				1422	<ul>
				1423	<li>fixes a couple of bugs in the 2.1.0 packaging</li>
				1424	<li>improvements on the HTML parser</li>
				1425	</ul>
				1426
Daniel Veillard	3f6f7f6	2000-06-30 17:58:25 +0000	[diff] [blame]	1427	<h3>2.1.0 and 1.8.8: June 29 2000</h3>
				1428	<ul>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1429	<li>1.8.8 is mostly a commodity package for upgrading to libxml2 according
				1430	to <a href="upgrade.html">new instructions</a>. It fixes a nasty problem
Daniel Veillard	3f6f7f6	2000-06-30 17:58:25 +0000	[diff] [blame]	1431	about &#38; charref parsing</li>
				1432	<li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
				1433	also contains numerous fixes and enhancements:
				1434	<ul>
				1435	<li>added xmlStopParser() to stop parsing</li>
				1436	<li>improved a lot parsing speed when there is large CDATA blocs</li>
				1437	<li>includes XPath patches provided by Picdar Technology</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1438	<li>tried to fix as much as possible DTD validation and namespace
Daniel Veillard	3f6f7f6	2000-06-30 17:58:25 +0000	[diff] [blame]	1439	related problems</li>
				1440	<li>output to a given encoding has been added/tested</li>
				1441	<li>lot of various fixes</li>
				1442	</ul>
				1443	</li>
				1444	</ul>
				1445
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1446	<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1447	<ul>
				1448	<li>First public release of libxml2. If you are using libxml, it's a good
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1449	idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially
				1450	scheduled for Apr 3 the release occurred only on Apr 12 due to massive
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1451	workload.</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1452	<li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1453	$prefix/include/gnome-xml), they also are referenced by
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1454	<pre>#include <libxml/xxx.h></pre>
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1455	<p>instead of</p>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1456	<pre>#include "xxx.h"</pre>
				1457	</li>
Daniel Veillard	8f62198	2000-03-20 13:07:15 +0000	[diff] [blame]	1458	<li>a new URI module for parsing URIs and following strictly RFC 2396</li>
				1459	<li>the memory allocation routines used by libxml can now be overloaded
				1460	dynamically by using xmlMemSetup()</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1461	<li>The previously CVS only tool tester has been renamed
				1462	<strong>xmllint</strong> and is now installed as part of the libxml2
				1463	package</li>
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1464	<li>The I/O interface has been revamped. There is now ways to plug in
				1465	specific I/O modules, either at the URI scheme detection level using
				1466	xmlRegisterInputCallbacks() or by passing I/O functions when creating a
				1467	parser context using xmlCreateIOParserCtxt()</li>
				1468	<li>there is a C preprocessor macro LIBXML_VERSION providing the version
				1469	number of the libxml module in use</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1470	<li>a number of optional features of libxml can now be excluded at
				1471	configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1472	</ul>
				1473
				1474	<h3>2.0.0beta: Mar 14 2000</h3>
				1475	<ul>
				1476	<li>This is a first Beta release of libxml version 2</li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1477	<li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
				1478	FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
				1479	RPMs</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1480	<li>This version is now the head in the Gnome CVS base, the old one is
				1481	available under the tag LIB_XML_1_X</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1482	<li>This includes a very large set of changes. From a programmatic point
				1483	of view applications should not have to be modified too much, check the
				1484	<a href="upgrade.html">upgrade page</a></li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1485	<li>Some interfaces may changes (especially a bit about encoding).</li>
				1486	<li>the updates includes:
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1487	<ul>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1488	<li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
				1489	handled now</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1490	<li>Better handling of entities, especially well-formedness checking
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1491	and proper PEref extensions in external subsets</li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1492	<li>DTD conditional sections</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1493	<li>Validation now correctly handle entities content</li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1494	<li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1495	structures to accommodate DOM</a></li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1496	</ul>
				1497	</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1498	<li>Serious progress were made toward compliance, <a
				1499	href="conf/result.html">here are the result of the test</a> against the
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1500	OASIS testsuite (except the Japanese tests since I don't support that
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1501	encoding yet). This URL is rebuilt every couple of hours using the CVS
				1502	head version.</li>
Daniel Veillard	e41f2b7	2000-01-30 20:00:07 +0000	[diff] [blame]	1503	</ul>
				1504
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1505	<h3>1.8.7: Mar 6 2000</h3>
				1506	<ul>
				1507	<li>This is a bug fix release:</li>
				1508	<li>It is possible to disable the ignorable blanks heuristic used by
				1509	libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1510	that for adherence to XML spec, this behaviour will be disabled by
				1511	default in 2.x . The same function will allow to keep compatibility for
				1512	old code.</li>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1513	<li>Blanks in <a> </a> constructs are not ignored anymore,
				1514	avoiding heuristic is really the Right Way :-\</li>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1515	<li>The unchecked use of snprintf which was breaking libxml-1.8.6
				1516	compilation on some platforms has been fixed</li>
				1517	<li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
				1518	URIs</li>
				1519	</ul>
				1520
Daniel Veillard	e41f2b7	2000-01-30 20:00:07 +0000	[diff] [blame]	1521	<h3>1.8.6: Jan 31 2000</h3>
				1522	<ul>
				1523	<li>added a nanoFTP transport module, debugged until the new version of <a
				1524	href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
				1525	it without troubles</li>
Daniel Veillard	da07c34	2000-01-25 18:31:22 +0000	[diff] [blame]	1526	</ul>
				1527
				1528	<h3>1.8.5: Jan 21 2000</h3>
				1529	<ul>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	1530	<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]	1531	href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
				1532	XML spec)</li>
Daniel Veillard	461a66c	2000-01-18 18:01:01 +0000	[diff] [blame]	1533	<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]	1534	<li>Jody Goldberg <jgoldberg@home.com> provided another patch trying
				1535	to solve the zlib checks problems</li>
Daniel Veillard	461a66c	2000-01-18 18:01:01 +0000	[diff] [blame]	1536	<li>The current state in gnome CVS base is expected to ship as 1.8.5 with
				1537	gnumeric soon</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	1538	</ul>
				1539
				1540	<h3>1.8.4: Jan 13 2000</h3>
				1541	<ul>
				1542	<li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
				1543	<li>all exit() call should have been removed from libxml</li>
				1544	<li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
				1545	<li>added newDocFragment()</li>
Daniel Veillard	f84f71f	2000-01-05 19:54:23 +0000	[diff] [blame]	1546	</ul>
				1547
				1548	<h3>1.8.3: Jan 5 2000</h3>
				1549	<ul>
				1550	<li>a Push interface for the XML and HTML parsers</li>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1551	<li>a shell-like interface to the document tree (try tester --shell :-)</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1552	<li>lots of bug fixes and improvement added over XMas holidays</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1553	<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]	1554	<li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
				1555	<li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1556	<li>External entity loading code has been revamped, now it uses
Daniel Veillard	f84f71f	2000-01-05 19:54:23 +0000	[diff] [blame]	1557	xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1558	<li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	1559	</ul>
				1560
				1561	<h3>1.8.2: Dec 21 1999</h3>
				1562	<ul>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1563	<li>I got another problem with includes and C++, I hope this issue is fixed
				1564	for good this time</li>
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	1565	<li>Added a few tree modification functions: xmlReplaceNode,
				1566	xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
				1567	xmlDocSetRootElement</li>
				1568	<li>Tried to improve the HTML output with help from <a
				1569	href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillard	e4e5131	1999-12-18 15:32:46 +0000	[diff] [blame]	1570	</ul>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1571
Daniel Veillard	e4e5131	1999-12-18 15:32:46 +0000	[diff] [blame]	1572	<h3>1.8.1: Dec 18 1999</h3>
				1573	<ul>
				1574	<li>various patches to avoid troubles when using libxml with C++ compilers
				1575	the "namespace" keyword and C escaping in include files</li>
				1576	<li>a problem in one of the core macros IS_CHAR was corrected</li>
				1577	<li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
				1578	and more specifically the Dia application</li>
Daniel Veillard	944b5ff	1999-12-15 19:08:24 +0000	[diff] [blame]	1579	<li>fixed a posteriori validation (validation after parsing, or by using a
				1580	Dtd not specified in the original document)</li>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1581	<li>fixed a bug in</li>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	1582	</ul>
				1583
				1584	<h3>1.8.0: Dec 12 1999</h3>
				1585	<ul>
				1586	<li>cleanup, especially memory wise</li>
				1587	<li>the parser should be more reliable, especially the HTML one, it should
				1588	not crash, whatever the input !</li>
				1589	<li>Integrated various patches, especially a speedup improvement for large
				1590	dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
				1591	configure with --with-buffers to enable them.</li>
				1592	<li>attribute normalization, oops should have been added long ago !</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1593	<li>attributes defaulted from DTDs should be available, xmlSetProp() now
				1594	does entities escaping by default.</li>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	1595	</ul>
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1596
				1597	<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1598	<ul>
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1599	<li>Lots of HTML improvement</li>
				1600	<li>Fixed some errors when saving both XML and HTML</li>
				1601	<li>More examples, the regression tests should now look clean</li>
				1602	<li>Fixed a bug with contiguous charref</li>
				1603	</ul>
				1604
				1605	<h3>1.7.3: Sep 29 1999</h3>
				1606	<ul>
				1607	<li>portability problems fixed</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1608	<li>snprintf was used unconditionally, leading to link problems on system
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1609	were it's not available, fixed</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1610	</ul>
				1611
				1612	<h3>1.7.1: Sep 24 1999</h3>
				1613	<ul>
				1614	<li>The basic type for strings manipulated by libxml has been renamed in
				1615	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]	1616	is that CHAR was conflicting with a predefined type on Windows. However
				1617	on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1618	<strong>#define </strong>.</li>
				1619	<li>Changed another error : the use of a structure field called errno, and
				1620	leading to troubles on platforms where it's a macro</li>
				1621	</ul>
				1622
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1623	<h3>1.7.0: Sep 23 1999</h3>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1624	<ul>
				1625	<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]	1626	href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1627	<li>Added an errno to report errors by another mean than a simple printf
				1628	like callback</li>
				1629	<li>Finished ID/IDREF support and checking when validation</li>
				1630	<li>Serious memory leaks fixed (there is now a <a
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	1631	href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1632	<li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
				1633	implementation</li>
				1634	<li>Added an HTML parser front-end</li>
				1635	</ul>
				1636
				1637	<h2><a name="XML">XML</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	1638
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	1639	<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]	1640	markup-based structured documents. Here is <a name="example">an example XML
				1641	document</a>:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1642	<pre><?xml version="1.0"?>
				1643	<EXAMPLE prop1="gnome is great" prop2="&amp; linux too">
				1644	<head>
				1645	<title>Welcome to Gnome</title>
				1646	</head>
				1647	<chapter>
				1648	<title>The Linux adventure</title>
				1649	<p>bla bla bla ...</p>
				1650	<image href="linus.gif"/>
				1651	<p>...</p>
				1652	</chapter>
				1653	</EXAMPLE></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	1654
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1655	<p>The first line specifies that it is an XML document and gives useful
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1656	information about its encoding. Then the rest of the document is a text
				1657	format whose structure is specified by tags between brackets. <strong>Each
				1658	tag opened has to be closed</strong>. XML is pedantic about this. However, if
				1659	a tag is empty (no content), a single tag can serve as both the opening and
				1660	closing tag if it ends with <code>/></code> rather than with
				1661	<code>></code>. Note that, for example, the image tag has no content (just
				1662	an attribute) and is closed by ending the tag with <code>/></code>.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	1663
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1664	<p>XML can be applied successfully to a wide range of tasks, ranging from
				1665	long term structured document maintenance (where it follows the steps of
				1666	SGML) to simple data encoding mechanisms like configuration file formatting
				1667	(glade), spreadsheets (gnumeric), or even shorter lived documents such as
				1668	WebDAV where it is used to encode remote calls between a client and a
				1669	server.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	1670
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1671	<h2><a name="XSLT">XSLT</a></h2>
				1672
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1673	<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
				1674
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1675	<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
				1676	language for transforming XML documents into other XML documents (or
				1677	HTML/textual output).</p>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1678
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	1679	<p>A separate library called libxslt is available implementing XSLT-1.0
				1680	for libxml2. This module "libxslt" too can be found in the Gnome CVS base.</p>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1681
Daniel Veillard	383b147	2001-01-23 11:39:52 +0000	[diff] [blame]	1682	<p>You can check the <a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1683	href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
				1684	supported and the progresses on the <a
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1685	href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog"
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1686	name="Changelog">Changelog</a>.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1687
				1688	<h2><a name="Python">Python and bindings</a></h2>
				1689
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1690	<p>There are a number of language bindings and wrappers available for
				1691	libxml2, the list below is not exhaustive. Please contact the <a
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1692	href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
				1693	(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
				1694	order to get updates to this list or to discuss the specific topic of libxml2
				1695	or libxslt wrappers or bindings:</p>
				1696	<ul>
Daniel Veillard	c14401e	2002-11-20 14:28:17 +0000	[diff] [blame]	1697	<li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
				1698	most up-to-date C++ bindings for libxml2, check the <a
				1699	href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
				1700	and the <a
				1701	href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1702	<li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1703	based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
Daniel Veillard	9b6fd30	2002-05-13 12:06:47 +0000	[diff] [blame]	1704	<li>and a third C++ wrapper by Peter Jones <pjones@pmade.org>
				1705	<p>Website: <a
				1706	href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
				1707	</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1708	<li><a
				1709	href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1710	Sergeant</a> developed <a
				1711	href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1712	libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1713	application server</a>.</li>
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	1714	<li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1715	earlier version of the libxml/libxslt <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1716	href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	1717	<li>Gopal.V and Peter Minten develop <a
				1718	href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1719	C# libxml2 bindings.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1720	<li>Petr Kozelka provides <a
				1721	href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1722	libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
Daniel Veillard	b2fb8ed	2002-04-01 09:33:12 +0000	[diff] [blame]	1723	<li>Uwe Fechner also provides <a
				1724	href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1725	implementation for Kylix2/D5/D6 from Borland.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1726	<li>Wai-Sun "Squidster" Chia provides <a
				1727	href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
				1728	libxml2 bindings are also available in Ruby through the <a
				1729	href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
				1730	maintained by Tobias Peters.</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1731	<li>Steve Ball and contributors maintains <a
				1732	href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1733	Tcl</a>.</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1734	<li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard	41b01a8	2003-02-27 11:09:06 +0000	[diff] [blame]	1735	<li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	1736	an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and
				1737	libxslt as part of GNU ClasspathX project.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1738	</ul>
				1739
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1740	<p>The distribution includes a set of Python bindings, which are guaranteed
				1741	to be maintained as part of the library in the future, though the Python
Daniel Veillard	41b01a8	2003-02-27 11:09:06 +0000	[diff] [blame]	1742	interface have not yet reached the completeness of the C API.</p>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1743
Daniel Veillard	27907c7	2002-12-16 16:05:58 +0000	[diff] [blame]	1744	<p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1745	maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port
				1746	of the Python bindings</a>.</p>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1747
Daniel Veillard	7ef0fcb	2002-12-14 10:38:55 +0000	[diff] [blame]	1748	<p>Note to people interested in building bindings, the API is formalized as
				1749	<a href="libxml2-api.xml">an XML API description file</a> which allows to
				1750	automate a large part of the Python bindings, this includes function
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1751	descriptions, enums, structures, typedefs, etc... The Python script used to
				1752	build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillard	7ef0fcb	2002-12-14 10:38:55 +0000	[diff] [blame]	1753
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1754	<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard	0b79dfe	2002-02-23 13:02:31 +0000	[diff] [blame]	1755	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1756	<li>If you use an RPM based distribution, simply install the <a
				1757	href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
				1758	RPM</a> (and if needed the <a
				1759	href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
				1760	RPM</a>).</li>
				1761	<li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
				1762	module distribution</a> corresponding to your installed version of
				1763	libxml2 and libxslt. Note that to install it you will need both libxml2
				1764	and libxslt installed and run "python setup.py build install" in the
				1765	module tree.</li>
Daniel Veillard	0b79dfe	2002-02-23 13:02:31 +0000	[diff] [blame]	1766	</ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1767
				1768	<p>The distribution includes a set of examples and regression tests for the
				1769	python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1770	excerpts from those tests:</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1771
				1772	<h3>tst.py:</h3>
				1773
				1774	<p>This is a basic test of the file interface and DOM navigation:</p>
				1775	<pre>import libxml2
				1776
				1777	doc = libxml2.parseFile("tst.xml")
				1778	if doc.name != "tst.xml":
				1779	print "doc.name failed"
				1780	sys.exit(1)
				1781	root = doc.children
				1782	if root.name != "doc":
				1783	print "root.name failed"
				1784	sys.exit(1)
				1785	child = root.children
				1786	if child.name != "foo":
				1787	print "child.name failed"
				1788	sys.exit(1)
				1789	doc.freeDoc()</pre>
				1790
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1791	<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1792	xmlParseFile (most of the bindings are automatically generated, and the xml
				1793	prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1794	binding level share the same subset of accessors:</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1795	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1796	<li><code>name</code> : returns the node name</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1797	<li><code>type</code> : returns a string indicating the node type</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1798	<li><code>content</code> : returns the content of the node, it is based on
				1799	xmlNodeGetContent() and hence is recursive.</li>
				1800	<li><code>parent</code> , <code>children</code>, <code>last</code>,
				1801	<code>next</code>, <code>prev</code>, <code>doc</code>,
				1802	<code>properties</code>: pointing to the associated element in the tree,
				1803	those may return None in case no such link exists.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1804	</ul>
				1805
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1806	<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1807	Reference counting for libxml2 trees would need quite a lot of work to
				1808	function properly, and rather than risk memory leaks if not implemented
				1809	correctly it sounds safer to have an explicit function to free a tree. The
				1810	wrapper python objects like doc, root or child are them automatically garbage
				1811	collected.</p>
				1812
				1813	<h3>validate.py:</h3>
				1814
				1815	<p>This test check the validation interfaces and redirection of error
				1816	messages:</p>
				1817	<pre>import libxml2
				1818
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1819	#deactivate error messages from the validation
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1820	def noerr(ctx, str):
				1821	pass
				1822
				1823	libxml2.registerErrorHandler(noerr, None)
				1824
				1825	ctxt = libxml2.createFileParserCtxt("invalid.xml")
				1826	ctxt.validate(1)
				1827	ctxt.parseDocument()
				1828	doc = ctxt.doc()
				1829	valid = ctxt.isValid()
				1830	doc.freeDoc()
				1831	if valid != 0:
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1832	print "validity check failed"</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1833
				1834	<p>The first thing to notice is the call to registerErrorHandler(), it
				1835	defines a new error handler global to the library. It is used to avoid seeing
				1836	the error messages when trying to validate the invalid document.</p>
				1837
				1838	<p>The main interest of that test is the creation of a parser context with
				1839	createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1840	parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1841	are also available using context methods.</p>
				1842
				1843	<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
				1844	C function interfaces in terms of objects method as much as possible. The
				1845	best to get a complete view of what methods are supported is to look at the
				1846	libxml2.py module containing all the wrappers.</p>
				1847
				1848	<h3>push.py:</h3>
				1849
				1850	<p>This test show how to activate the push parser interface:</p>
				1851	<pre>import libxml2
				1852
				1853	ctxt = libxml2.createPushParser(None, "<foo", 4, "test.xml")
				1854	ctxt.parseChunk("/>", 2, 1)
				1855	doc = ctxt.doc()
				1856
				1857	doc.freeDoc()</pre>
				1858
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1859	<p>The context is created with a special call based on the
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1860	xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1861	SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1862	the resource in case URI-References need to be computed by the parser.</p>
				1863
				1864	<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1865	setting the third argument terminate to 1.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1866
				1867	<h3>pushSAX.py:</h3>
				1868
				1869	<p>this test show the use of the event based parsing interfaces. In this case
				1870	the parser does not build a document, but provides callback information as
				1871	the parser makes progresses analyzing the data being provided:</p>
				1872	<pre>import libxml2
				1873	log = ""
				1874
				1875	class callback:
				1876	def startDocument(self):
				1877	global log
				1878	log = log + "startDocument:"
				1879
				1880	def endDocument(self):
				1881	global log
				1882	log = log + "endDocument:"
				1883
				1884	def startElement(self, tag, attrs):
				1885	global log
				1886	log = log + "startElement %s %s:" % (tag, attrs)
				1887
				1888	def endElement(self, tag):
				1889	global log
				1890	log = log + "endElement %s:" % (tag)
				1891
				1892	def characters(self, data):
				1893	global log
				1894	log = log + "characters: %s:" % (data)
				1895
				1896	def warning(self, msg):
				1897	global log
				1898	log = log + "warning: %s:" % (msg)
				1899
				1900	def error(self, msg):
				1901	global log
				1902	log = log + "error: %s:" % (msg)
				1903
				1904	def fatalError(self, msg):
				1905	global log
				1906	log = log + "fatalError: %s:" % (msg)
				1907
				1908	handler = callback()
				1909
				1910	ctxt = libxml2.createPushParser(handler, "<foo", 4, "test.xml")
				1911	chunk = " url='tst'>b"
				1912	ctxt.parseChunk(chunk, len(chunk), 0)
				1913	chunk = "ar</foo>"
				1914	ctxt.parseChunk(chunk, len(chunk), 1)
				1915
Daniel Veillard	fcbfa2d	2002-02-21 17:54:27 +0000	[diff] [blame]	1916	reference = "startDocument:startElement foo {'url': 'tst'}:" + \
				1917	"characters: bar:endElement foo:endDocument:"
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1918	if log != reference:
				1919	print "Error got: %s" % log
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1920	print "Expected: %s" % reference</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1921
				1922	<p>The key object in that test is the handler, it provides a number of entry
				1923	points which can be called by the parser as it makes progresses to indicate
				1924	the information set obtained. The full set of callback is larger than what
				1925	the callback class in that specific example implements (see the SAX
				1926	definition for a complete list). The wrapper will only call those supplied by
				1927	the object when activated. The startElement receives the names of the element
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1928	and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1929
				1930	<p>Also note that the reference string generated from the callback shows a
				1931	single character call even though the string "bar" is passed to the parser
				1932	from 2 different call to parseChunk()</p>
				1933
				1934	<h3>xpath.py:</h3>
				1935
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1936	<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1937	<pre>import libxml2
				1938
				1939	doc = libxml2.parseFile("tst.xml")
				1940	ctxt = doc.xpathNewContext()
				1941	res = ctxt.xpathEval("//*")
				1942	if len(res) != 2:
				1943	print "xpath query: wrong node set size"
				1944	sys.exit(1)
				1945	if res[0].name != "doc" or res[1].name != "foo":
				1946	print "xpath query: wrong node set value"
				1947	sys.exit(1)
				1948	doc.freeDoc()
				1949	ctxt.xpathFreeContext()</pre>
				1950
				1951	<p>This test parses a file, then create an XPath context to evaluate XPath
				1952	expression on it. The xpathEval() method execute an XPath query and returns
				1953	the result mapped in a Python way. String and numbers are natively converted,
				1954	and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1955	the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1956	the result of the XPath query may point back to the document tree and hence
				1957	the document must be freed after the result of the query is used.</p>
				1958
				1959	<h3>xpathext.py:</h3>
				1960
				1961	<p>This test shows how to extend the XPath engine with functions written in
				1962	python:</p>
				1963	<pre>import libxml2
				1964
				1965	def foo(ctx, x):
				1966	return x + 1
				1967
				1968	doc = libxml2.parseFile("tst.xml")
				1969	ctxt = doc.xpathNewContext()
				1970	libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)
				1971	res = ctxt.xpathEval("foo(1)")
				1972	if res != 2:
				1973	print "xpath extension failure"
				1974	doc.freeDoc()
				1975	ctxt.xpathFreeContext()</pre>
				1976
				1977	<p>Note how the extension function is registered with the context (but that
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1978	part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1979
				1980	<h3>tstxpath.py:</h3>
				1981
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1982	<p>This test is similar to the previous one but shows how the extension
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1983	function can access the XPath evaluation context:</p>
				1984	<pre>def foo(ctx, x):
				1985	global called
				1986
				1987	#
				1988	# test that access to the XPath evaluation contexts
				1989	#
				1990	pctxt = libxml2.xpathParserContext(_obj=ctx)
				1991	ctxt = pctxt.context()
				1992	called = ctxt.function()
				1993	return x + 1</pre>
				1994
				1995	<p>All the interfaces around the XPath parser(or rather evaluation) context
				1996	are not finalized, but it should be sufficient to do contextual work at the
				1997	evaluation point.</p>
				1998
				1999	<h3>Memory debugging:</h3>
				2000
				2001	<p>last but not least, all tests starts with the following prologue:</p>
				2002	<pre>#memory debug specific
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2003	libxml2.debugMemory(1)</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	2004
				2005	<p>and ends with the following epilogue:</p>
				2006	<pre>#memory debug specific
				2007	libxml2.cleanupParser()
				2008	if libxml2.debugMemory(1) == 0:
				2009	print "OK"
				2010	else:
				2011	print "Memory leak %d bytes" % (libxml2.debugMemory(1))
				2012	libxml2.dumpMemory()</pre>
				2013
				2014	<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2015	allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	2016	library state and checks that all allocated memory has been freed. If not it
				2017	calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	2018
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2019	<h2><a name="architecture">libxml2 architecture</a></h2>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2020
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2021	<p>Libxml2 is made of multiple components; some of them are optional, and most
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	2022	of the block interfaces are public. The main components are:</p>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2023	<ul>
				2024	<li>an Input/Output layer</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	2025	<li>FTP and HTTP client layers (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2026	<li>an Internationalization layer managing the encodings support</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	2027	<li>a URI module</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2028	<li>the XML parser and its basic SAX interface</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	2029	<li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2030	<li>a SAX tree module to build an in-memory DOM representation</li>
				2031	<li>a tree module to manipulate the DOM representation</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	2032	<li>a validation module using the DOM representation (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2033	<li>an XPath module for global lookup in a DOM representation
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	2034	(optional)</li>
				2035	<li>a debug module (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	2036	</ul>
				2037
				2038	<p>Graphically this gives the following:</p>
				2039
				2040	<p><img src="libxml.gif" alt="a graphical view of the various"></p>
				2041
				2042	<p></p>
				2043
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	2044	<h2><a name="tree">The tree output</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	2045
				2046	<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]	2047	returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	2048	<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	2049	as the file name, the document type, and a <strong>children</strong> pointer
				2050	which is the root of the document (or more exactly the first child under the
				2051	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]	2052	chained in double-linked lists of siblings and with a children<->parent
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	2053	relationship. An xmlNode can also carry properties (a chain of xmlAttr
				2054	structures). An attribute may have a value which is a list of TEXT or
				2055	ENTITY_REF nodes.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	2056
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2057	<p>Here is an example (erroneous with respect to the XML spec since there
				2058	should be only one ELEMENT under the root):</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	2059
				2060	<p><img src="structure.gif" alt=" structure.gif "></p>
				2061
				2062	<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]	2063	called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	2064	prints them back as parsed. This is useful for detecting errors both in XML
				2065	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]	2066	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]	2067	result with the <a href="#example">example</a> given before:</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2068	<pre>DOCUMENT
				2069	version=1.0
				2070	standalone=true
				2071	ELEMENT EXAMPLE
				2072	ATTRIBUTE prop1
				2073	TEXT
				2074	content=gnome is great
				2075	ATTRIBUTE prop2
				2076	ENTITY_REF
				2077	TEXT
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	2078	content= linux too
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	2079	ELEMENT head
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2080	ELEMENT title
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2081	TEXT
				2082	content=Welcome to Gnome
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2083	ELEMENT chapter
				2084	ELEMENT title
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2085	TEXT
				2086	content=The Linux adventure
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2087	ELEMENT p
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2088	TEXT
				2089	content=bla bla bla ...
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2090	ELEMENT image
				2091	ATTRIBUTE href
				2092	TEXT
				2093	content=linus.gif
				2094	ELEMENT p
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2095	TEXT
				2096	content=...</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	2097
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2098	<p>This should be useful for learning the internal representation model.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	2099
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	2100	<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2101
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	2102	<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]	2103	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]	2104	loaded using libxml), it's better to use the SAX interface of libxml. SAX is
				2105	a <strong>callback-based interface</strong> to the parser. Before parsing,
				2106	the application layer registers a customized set of callbacks which are
				2107	called by the library as it progresses through the XML input.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2108
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2109	<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]	2110	libxml, see the <a
				2111	href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
				2112	documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2113	Henstridge</a>.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2114
				2115	<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
				2116	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]	2117	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]	2118	distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2119	testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2120	<pre>SAX.setDocumentLocator()
				2121	SAX.startDocument()
				2122	SAX.getEntity(amp)
				2123	SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp; linux too')
				2124	SAX.characters( , 3)
				2125	SAX.startElement(head)
				2126	SAX.characters( , 4)
				2127	SAX.startElement(title)
				2128	SAX.characters(Welcome to Gnome, 16)
				2129	SAX.endElement(title)
				2130	SAX.characters( , 3)
				2131	SAX.endElement(head)
				2132	SAX.characters( , 3)
				2133	SAX.startElement(chapter)
				2134	SAX.characters( , 4)
				2135	SAX.startElement(title)
				2136	SAX.characters(The Linux adventure, 19)
				2137	SAX.endElement(title)
				2138	SAX.characters( , 4)
				2139	SAX.startElement(p)
				2140	SAX.characters(bla bla bla ..., 15)
				2141	SAX.endElement(p)
				2142	SAX.characters( , 4)
				2143	SAX.startElement(image, href='linus.gif')
				2144	SAX.endElement(image)
				2145	SAX.characters( , 4)
				2146	SAX.startElement(p)
				2147	SAX.characters(..., 3)
				2148	SAX.endElement(p)
				2149	SAX.characters( , 3)
				2150	SAX.endElement(chapter)
				2151	SAX.characters( , 1)
				2152	SAX.endElement(EXAMPLE)
				2153	SAX.endDocument()</pre>
				2154
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2155	<p>Most of the other interfaces of libxml2 are based on the DOM tree-building
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	2156	facility, so nearly everything up to the end of this document presupposes the
				2157	use of the standard DOM tree build. Note that the DOM tree itself is built by
				2158	a set of registered default callbacks, without internal specific
				2159	interface.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2160
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2161	<h2><a name="Validation">Validation & DTDs</a></h2>
				2162
				2163	<p>Table of Content:</p>
				2164	<ol>
				2165	<li><a href="#General5">General overview</a></li>
				2166	<li><a href="#definition">The definition</a></li>
				2167	<li><a href="#Simple">Simple rules</a>
				2168	<ol>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	2169	<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]	2170	<li><a href="#Declaring">Declaring elements</a></li>
				2171	<li><a href="#Declaring1">Declaring attributes</a></li>
				2172	</ol>
				2173	</li>
				2174	<li><a href="#Some">Some examples</a></li>
				2175	<li><a href="#validate">How to validate</a></li>
				2176	<li><a href="#Other">Other resources</a></li>
				2177	</ol>
				2178
				2179	<h3><a name="General5">General overview</a></h3>
				2180
				2181	<p>Well what is validation and what is a DTD ?</p>
				2182
				2183	<p>DTD is the acronym for Document Type Definition. This is a description of
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2184	the content for a family of XML files. This is part of the XML 1.0
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2185	specification, and allows one to describe and verify that a given document
				2186	instance conforms to the set of rules detailing its structure and content.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2187
				2188	<p>Validation is the process of checking a document against a DTD (more
				2189	generally against a set of construction rules).</p>
				2190
				2191	<p>The validation process and building DTDs are the two most difficult parts
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2192	of the XML life cycle. Briefly a DTD defines all the possible elements to be
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2193	found within your document, what is the formal shape of your document tree
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2194	(by defining the allowed content of an element; either text, a regular
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2195	expression for the allowed list of children, or mixed content i.e. both text
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2196	and children). The DTD also defines the valid attributes for all elements and
				2197	the types of those attributes.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2198
				2199	<h3><a name="definition1">The definition</a></h3>
				2200
				2201	<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
				2202	href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
				2203	Rev1</a>):</p>
				2204	<ul>
				2205	<li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
				2206	elements</a></li>
				2207	<li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
				2208	attributes</a></li>
				2209	</ul>
				2210
				2211	<p>(unfortunately) all this is inherited from the SGML world, the syntax is
				2212	ancient...</p>
				2213
				2214	<h3><a name="Simple1">Simple rules</a></h3>
				2215
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2216	<p>Writing DTDs can be done in many ways. The rules to build them if you need
				2217	something permanent or something which can evolve over time can be radically
				2218	different. Really complex DTDs like DocBook ones are flexible but quite
				2219	harder to design. I will just focus on DTDs for a formats with a fixed simple
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2220	structure. It is just a set of basic rules, and definitely not exhaustive nor
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2221	usable for complex DTD design.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2222
				2223	<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
				2224
				2225	<p>Assuming the top element of the document is <code>spec</code> and the dtd
				2226	is placed in the file <code>mydtd</code> in the subdirectory
				2227	<code>dtds</code> of the directory from where the document were loaded:</p>
				2228
				2229	<p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p>
				2230
				2231	<p>Notes:</p>
				2232	<ul>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2233	<li>The system string is actually an URI-Reference (as defined in <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2234	href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2235	full URL string indicating the location of your DTD on the Web. This is a
				2236	really good thing to do if you want others to validate your document.</li>
				2237	<li>It is also possible to associate a <code>PUBLIC</code> identifier (a
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2238	magic string) so that the DTD is looked up in catalogs on the client side
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2239	without having to locate it on the web.</li>
				2240	<li>A DTD contains a set of element and attribute declarations, but they
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2241	don't define what the root of the document should be. This is explicitly
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2242	told to the parser/validator as the first element of the
				2243	<code>DOCTYPE</code> declaration.</li>
				2244	</ul>
				2245
				2246	<h4><a name="Declaring2">Declaring elements</a>:</h4>
				2247
				2248	<p>The following declares an element <code>spec</code>:</p>
				2249
				2250	<p><code><!ELEMENT spec (front, body, back?)></code></p>
				2251
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2252	<p>It also expresses that the spec element contains one <code>front</code>,
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2253	one <code>body</code> and one optional <code>back</code> children elements in
				2254	this order. The declaration of one element of the structure and its content
				2255	are done in a single declaration. Similarly the following declares
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2256	<code>div1</code> elements:</p>
				2257
Daniel Veillard	5173727	2002-01-23 23:10:38 +0000	[diff] [blame]	2258	<p><code><!ELEMENT div1 (head, (p \| list \| note)*, div2?)></code></p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2259
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2260	<p>which means div1 contains one <code>head</code> then a series of optional
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2261	<code>p</code>, <code>list</code>s and <code>note</code>s and then an
				2262	optional <code>div2</code>. And last but not least an element can contain
				2263	text:</p>
				2264
				2265	<p><code><!ELEMENT b (#PCDATA)></code></p>
				2266
				2267	<p><code>b</code> contains text or being of mixed content (text and elements
				2268	in no particular order):</p>
				2269
				2270	<p><code><!ELEMENT p (#PCDATA\|a\|ul\|b\|i\|em)*></code></p>
				2271
				2272	<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
				2273	<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
				2274	order.</p>
				2275
				2276	<h4><a name="Declaring1">Declaring attributes</a>:</h4>
				2277
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2278	<p>Again the attributes declaration includes their content definition:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2279
				2280	<p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p>
				2281
				2282	<p>means that the element <code>termdef</code> can have a <code>name</code>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2283	attribute containing text (<code>CDATA</code>) and which is optional
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2284	(<code>#IMPLIED</code>). The attribute value can also be defined within a
				2285	set:</p>
				2286
				2287	<p><code><!ATTLIST list type (bullets\|ordered\|glossary)
				2288	"ordered"></code></p>
				2289
				2290	<p>means <code>list</code> element have a <code>type</code> attribute with 3
				2291	allowed values "bullets", "ordered" or "glossary" and which default to
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2292	"ordered" if the attribute is not explicitly specified.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2293
				2294	<p>The content type of an attribute can be text (<code>CDATA</code>),
				2295	anchor/reference/references
				2296	(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
				2297	(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
				2298	(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
				2299	<code>chapter</code> element can have an optional <code>id</code> attribute
				2300	of type <code>ID</code>, usable for reference from attribute of type
				2301	IDREF:</p>
				2302
				2303	<p><code><!ATTLIST chapter id ID #IMPLIED></code></p>
				2304
				2305	<p>The last value of an attribute definition can be <code>#REQUIRED
				2306	</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
				2307	meaning that it is optional, or the default value (possibly prefixed by
				2308	<code>#FIXED</code> if it is the only allowed).</p>
				2309
				2310	<p>Notes:</p>
				2311	<ul>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2312	<li>Usually the attributes pertaining to a given element are declared in a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2313	single expression, but it is just a convention adopted by a lot of DTD
				2314	writers:
				2315	<pre><!ATTLIST termdef
				2316	id ID #REQUIRED
				2317	name CDATA #IMPLIED></pre>
				2318	<p>The previous construct defines both <code>id</code> and
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2319	<code>name</code> attributes for the element <code>termdef</code>.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2320	</li>
				2321	</ul>
				2322
				2323	<h3><a name="Some1">Some examples</a></h3>
				2324
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2325	<p>The directory <code>test/valid/dtds/</code> in the libxml2 distribution
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2326	contains some complex DTD examples. The example in the file
				2327	<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is
				2328	directly included within the document.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2329
				2330	<h3><a name="validate1">How to validate</a></h3>
				2331
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2332	<p>The simplest way is to use the xmllint program included with libxml. The
				2333	<code>--valid</code> option turns-on validation of the files given as input.
				2334	For example the following validates a copy of the first revision of the XML
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2335	1.0 specification:</p>
				2336
				2337	<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
				2338
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2339	<p>the -- noout is used to disable output of the resulting tree.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2340
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2341	<p>The <code>--dtdvalid dtd</code> allows validation of the document(s)
				2342	against a given DTD.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2343
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2344	<p>Libxml2 exports an API to handle DTDs and validation, check the <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2345	href="http://xmlsoft.org/html/libxml-valid.html">associated
				2346	description</a>.</p>
				2347
				2348	<h3><a name="Other1">Other resources</a></h3>
				2349
				2350	<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
				2351	will just list one for now, others pointers welcome:</p>
				2352	<ul>
				2353	<li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
				2354	</ul>
				2355
				2356	<p>I suggest looking at the examples found under test/valid/dtd and any of
				2357	the large number of books available on XML. The dia example in test/valid
				2358	should be both simple and complete enough to allow you to build your own.</p>
				2359
				2360	<p></p>
				2361
				2362	<h2><a name="Memory">Memory Management</a></h2>
				2363
				2364	<p>Table of Content:</p>
				2365	<ol>
				2366	<li><a href="#General3">General overview</a></li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2367	<li><a href="#setting">Setting libxml2 set of memory routines</a></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2368	<li><a href="#cleanup">Cleaning up after parsing</a></li>
				2369	<li><a href="#Debugging">Debugging routines</a></li>
				2370	<li><a href="#General4">General memory requirements</a></li>
				2371	</ol>
				2372
				2373	<h3><a name="General3">General overview</a></h3>
				2374
				2375	<p>The module <code><a
				2376	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2377	provides the interfaces to the libxml2 memory system:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2378	<ul>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2379	<li>libxml2 does not use the libc memory allocator directly but xmlFree(),
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2380	xmlMalloc() and xmlRealloc()</li>
				2381	<li>those routines can be reallocated to a specific set of routine, by
				2382	default the libc ones i.e. free(), malloc() and realloc()</li>
				2383	<li>the xmlmemory.c module includes a set of debugging routine</li>
				2384	</ul>
				2385
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2386	<h3><a name="setting">Setting libxml2 set of memory routines</a></h3>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2387
				2388	<p>It is sometimes useful to not use the default memory allocator, either for
				2389	debugging, analysis or to implement a specific behaviour on memory management
				2390	(like on embedded systems). Two function calls are available to do so:</p>
				2391	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2392	<li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet
				2393	()</a> which return the current set of functions in use by the parser</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2394	<li><a
				2395	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2396	which allow to set up a new set of memory allocation functions</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2397	</ul>
				2398
				2399	<p>Of course a call to xmlMemSetup() should probably be done before calling
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2400	any other libxml2 routines (unless you are sure your allocations routines are
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2401	compatibles).</p>
				2402
				2403	<h3><a name="cleanup">Cleaning up after parsing</a></h3>
				2404
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2405	<p>Libxml2 is not stateless, there is a few set of memory structures needing
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2406	allocation before the parser is fully functional (some encoding structures
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2407	for example). This also mean that once parsing is finished there is a tiny
				2408	amount of memory (a few hundred bytes) which can be recollected if you don't
				2409	reuse the parser immediately:</p>
				2410	<ul>
				2411	<li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2412	()</a> is a centralized routine to free the parsing states. Note that it
				2413	won't deallocate any produced tree if any (use the xmlFreeDoc() and
				2414	related routines for this).</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2415	<li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2416	()</a> is the dual routine allowing to preallocate the parsing state
				2417	which can be useful for example to avoid initialization reentrancy
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2418	problems when using libxml2 in multithreaded applications</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2419	</ul>
				2420
				2421	<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
				2422	at the next invocation of parser routines, but be careful of the consequences
				2423	in multithreaded applications.</p>
				2424
				2425	<h3><a name="Debugging">Debugging routines</a></h3>
				2426
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2427	<p>When configured using --with-mem-debug flag (off by default), libxml2 uses
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2428	a set of memory allocation debugging routines keeping track of all allocated
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2429	blocks and the location in the code where the routine was called. A couple of
				2430	other debugging routines allow to dump the memory allocated infos to a file
				2431	or call a specific routine when a given block number is allocated:</p>
				2432	<ul>
				2433	<li><a
				2434	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2435	<a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2436	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
				2437	and <a
				2438	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
				2439	are the memory debugging replacement allocation routines</li>
				2440	<li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2441	()</a> dumps all the informations about the allocated memory block lefts
				2442	in the <code>.memdump</code> file</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2443	</ul>
				2444
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2445	<p>When developing libxml2 memory debug is enabled, the tests programs call
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2446	xmlMemoryDump () and the "make test" regression tests will check for any
				2447	memory leak during the full regression test sequence, this helps a lot
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2448	ensuring that libxml2 does not leak memory and bullet proof memory
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2449	allocations use (some libc implementations are known to be far too permissive
				2450	resulting in major portability problems!).</p>
				2451
				2452	<p>If the .memdump reports a leak, it displays the allocation function and
				2453	also tries to give some informations about the content and structure of the
				2454	allocated blocks left. This is sufficient in most cases to find the culprit,
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2455	but not always. Assuming the allocation problem is reproducible, it is
				2456	possible to find more easily:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2457	<ol>
				2458	<li>write down the block number xxxx not allocated</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2459	<li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest
Daniel Veillard	7579482	2002-04-11 16:24:32 +0000	[diff] [blame]	2460	when using GDB is to simply give the command
				2461	<p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p>
				2462	<p>before running the program.</p>
				2463	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2464	<li>run the program under a debugger and set a breakpoint on
				2465	xmlMallocBreakpoint() a specific function called when this precise block
				2466	is allocated</li>
				2467	<li>when the breakpoint is reached you can then do a fine analysis of the
				2468	allocation an step to see the condition resulting in the missing
				2469	deallocation.</li>
				2470	</ol>
				2471
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2472	<p>I used to use a commercial tool to debug libxml2 memory problems but after
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2473	noticing that it was not detecting memory leaks that simple mechanism was
Daniel Veillard	7579482	2002-04-11 16:24:32 +0000	[diff] [blame]	2474	used and proved extremely efficient until now. Lately I have also used <a
				2475	href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some
				2476	success, it is tied to the i386 architecture since it works by emulating the
				2477	processor and instruction set, it is slow but extremely efficient, i.e. it
				2478	spot memory usage errors in a very precise way.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2479
				2480	<h3><a name="General4">General memory requirements</a></h3>
				2481
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2482	<p>How much libxml2 memory require ? It's hard to tell in average it depends
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2483	of a number of things:</p>
				2484	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2485	<li>the parser itself should work in a fixed amount of memory, except for
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2486	information maintained about the stacks of names and entities locations.
				2487	The I/O and encoding handlers will probably account for a few KBytes.
				2488	This is true for both the XML and HTML parser (though the HTML parser
				2489	need more state).</li>
				2490	<li>If you are generating the DOM tree then memory requirements will grow
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2491	nearly linear with the size of the data. In general for a balanced
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2492	textual document the internal memory requirement is about 4 times the
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2493	size of the UTF8 serialization of this document (example the XML-1.0
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2494	recommendation is a bit more of 150KBytes and takes 650KBytes of main
				2495	memory when parsed). Validation will add a amount of memory required for
				2496	maintaining the external Dtd state which should be linear with the
				2497	complexity of the content model defined by the Dtd</li>
Daniel Veillard	ce192eb	2003-04-16 15:58:05 +0000	[diff] [blame]	2498	<li>If you need to work with fixed memory requirements or don't need the
				2499	full DOM tree then using the <a href="xmlreader.html">xmlReader
				2500	interface</a> is probably the best way to proceed, it still allows to
				2501	validate or operate on subset of the tree if needed.</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2502	<li>If you don't care about the advanced features of libxml2 like
Daniel Veillard	ce192eb	2003-04-16 15:58:05 +0000	[diff] [blame]	2503	validation, DOM, XPath or XPointer, don't use entities, need to work with
				2504	fixed memory requirements, and try to get the fastest parsing possible
				2505	then the SAX interface should be used, but it has known restrictions.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2506	</ul>
				2507
				2508	<p></p>
				2509
				2510	<h2><a name="Encodings">Encodings support</a></h2>
				2511
				2512	<p>Table of Content:</p>
				2513	<ol>
				2514	<li><a href="encoding.html#What">What does internationalization support
				2515	mean ?</a></li>
				2516	<li><a href="encoding.html#internal">The internal encoding, how and
				2517	why</a></li>
				2518	<li><a href="encoding.html#implemente">How is it implemented ?</a></li>
				2519	<li><a href="encoding.html#Default">Default supported encodings</a></li>
				2520	<li><a href="encoding.html#extend">How to extend the existing
				2521	support</a></li>
				2522	</ol>
				2523
				2524	<h3><a name="What">What does internationalization support mean ?</a></h3>
				2525
Daniel Veillard	238836e	2003-04-07 22:57:29 +0000	[diff] [blame]	2526	<p>If you are not really familiar with Internationalization (usual shorcut is
				2527	I18N) , Unicode, characters and glyphs, I suggest you read a <a
				2528	href="http://www.tbray.org/ongoing/When/200x/2003/04/06/Unicode">presentation</a>
				2529	by Tim Bray on Unicode and why you should care about it.</p>
				2530
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2531	<p>XML was designed from the start to allow the support of any character set
				2532	by using Unicode. Any conformant XML parser has to support the UTF-8 and
				2533	UTF-16 default encodings which can both express the full unicode ranges. UTF8
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2534	is a variable length encoding whose greatest points are to reuse the same
				2535	encoding for ASCII and to save space for Western encodings, but it is a bit
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2536	more complex to handle in practice. UTF-16 use 2 bytes per characters (and
				2537	sometimes combines two pairs), it makes implementation easier, but looks a
				2538	bit overkill for Western languages encoding. Moreover the XML specification
				2539	allows document to be encoded in other encodings at the condition that they
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2540	are clearly labeled as such. For example the following is a wellformed XML
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2541	document encoded in ISO-8859 1 and using accentuated letter that we French
				2542	likes for both markup and content:</p>
				2543	<pre><?xml version="1.0" encoding="ISO-8859-1"?>
				2544	<très>là</très></pre>
				2545
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2546	<p>Having internationalization support in libxml2 means the following:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2547	<ul>
				2548	<li>the document is properly parsed</li>
				2549	<li>informations about it's encoding are saved</li>
				2550	<li>it can be modified</li>
				2551	<li>it can be saved in its original encoding</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2552	<li>it can also be saved in another encoding supported by libxml2 (for
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2553	example straight UTF8 or even an ASCII form)</li>
				2554	</ul>
				2555
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2556	<p>Another very important point is that the whole libxml2 API, with the
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2557	exception of a few routines to read with a specific encoding or save to a
				2558	specific encoding, is completely agnostic about the original encoding of the
				2559	document.</p>
				2560
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2561	<p>It should be noted too that the HTML parser embedded in libxml2 now obey
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2562	the same rules too, the following document will be (as of 2.2.2) handled in
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2563	an internationalized fashion by libxml2 too:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2564	<pre><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
				2565	"http://www.w3.org/TR/REC-html40/loose.dtd">
				2566	<html lang="fr">
				2567	<head>
				2568	<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1">
				2569	</head>
				2570	<body>
				2571	<p>W3C crée des standards pour le Web.</body>
				2572	</html></pre>
				2573
				2574	<h3><a name="internal">The internal encoding, how and why</a></h3>
				2575
				2576	<p>One of the core decision was to force all documents to be converted to a
				2577	default internal encoding, and that encoding to be UTF-8, here are the
				2578	rationale for those choices:</p>
				2579	<ul>
				2580	<li>keeping the native encoding in the internal form would force the libxml
				2581	users (or the code associated) to be fully aware of the encoding of the
				2582	original document, for examples when adding a text node to a document,
				2583	the content would have to be provided in the document encoding, i.e. the
				2584	client code would have to check it before hand, make sure it's conformant
				2585	to the encoding, etc ... Very hard in practice, though in some specific
				2586	cases this may make sense.</li>
				2587	<li>the second decision was which encoding. From the XML spec only UTF8 and
				2588	UTF16 really makes sense as being the two only encodings for which there
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2589	is mandatory support. UCS-4 (32 bits fixed size encoding) could be
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2590	considered an intelligent choice too since it's a direct Unicode mapping
				2591	support. I selected UTF-8 on the basis of efficiency and compatibility
				2592	with surrounding software:
				2593	<ul>
				2594	<li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
				2595	more costly to import and export CPU wise) is also far more compact
				2596	than UTF-16 (and UCS-4) for a majority of the documents I see it used
				2597	for right now (RPM RDF catalogs, advogato data, various configuration
				2598	file formats, etc.) and the key point for today's computer
				2599	architecture is efficient uses of caches. If one nearly double the
				2600	memory requirement to store the same amount of data, this will trash
				2601	caches (main memory/external caches/internal caches) and my take is
				2602	that this harms the system far more than the CPU requirements needed
				2603	for the conversion to UTF-8</li>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2604	<li>Most of libxml2 version 1 users were using it with straight ASCII
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2605	most of the time, doing the conversion with an internal encoding
				2606	requiring all their code to be rewritten was a serious show-stopper
				2607	for using UTF-16 or UCS-4.</li>
				2608	<li>UTF-8 is being used as the de-facto internal encoding standard for
				2609	related code like the <a href="http://www.pango.org/">pango</a>
				2610	upcoming Gnome text widget, and a lot of Unix code (yep another place
				2611	where Unix programmer base takes a different approach from Microsoft
				2612	- they are using UTF-16)</li>
				2613	</ul>
				2614	</li>
				2615	</ul>
				2616
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2617	<p>What does this mean in practice for the libxml2 user:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2618	<ul>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2619	<li>xmlChar, the libxml2 data type is a byte, those bytes must be assembled
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2620	as UTF-8 valid strings. The proper way to terminate an xmlChar * string
				2621	is simply to append 0 byte, as usual.</li>
				2622	<li>One just need to make sure that when using chars outside the ASCII set,
				2623	the values has been properly converted to UTF-8</li>
				2624	</ul>
				2625
				2626	<h3><a name="implemente">How is it implemented ?</a></h3>
				2627
				2628	<p>Let's describe how all this works within libxml, basically the I18N
				2629	(internationalization) support get triggered only during I/O operation, i.e.
				2630	when reading a document or saving one. Let's look first at the reading
				2631	sequence:</p>
				2632	<ol>
				2633	<li>when a document is processed, we usually don't know the encoding, a
				2634	simple heuristic allows to detect UTF-18 and UCS-4 from whose where the
				2635	ASCII range (0-0x7F) maps with ASCII</li>
				2636	<li>the xml declaration if available is parsed, including the encoding
				2637	declaration. At that point, if the autodetected encoding is different
				2638	from the one declared a call to xmlSwitchEncoding() is issued.</li>
				2639	<li>If there is no encoding declaration, then the input has to be in either
				2640	UTF-8 or UTF-16, if it is not then at some point when processing the
				2641	input, the converter/checker of UTF-8 form will raise an encoding error.
				2642	You may end-up with a garbled document, or no document at all ! Example:
				2643	<pre>~/XML -> ./xmllint err.xml
				2644	err.xml:1: error: Input is not proper UTF-8, indicate encoding !
				2645	<très>là</très>
				2646	^
				2647	err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
				2648	<très>là</très>
				2649	^</pre>
				2650	</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2651	<li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2652	then search the default registered encoding converters for that encoding.
				2653	If it's not within the default set and iconv() support has been compiled
				2654	it, it will ask iconv for such an encoder. If this fails then the parser
				2655	will report an error and stops processing:
				2656	<pre>~/XML -> ./xmllint err2.xml
				2657	err2.xml:1: error: Unsupported encoding UnsupportedEnc
				2658	<?xml version="1.0" encoding="UnsupportedEnc"?>
				2659	^</pre>
				2660	</li>
Daniel Veillard	46c5c1d	2002-05-20 07:15:54 +0000	[diff] [blame]	2661	<li>From that point the encoder processes progressively the input (it is
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2662	plugged as a front-end to the I/O module) for that entity. It captures
				2663	and convert on-the-fly the document to be parsed to UTF-8. The parser
				2664	itself just does UTF-8 checking of this input and process it
				2665	transparently. The only difference is that the encoding information has
				2666	been added to the parsing context (more precisely to the input
				2667	corresponding to this entity).</li>
				2668	<li>The result (when using DOM) is an internal form completely in UTF-8
				2669	with just an encoding information on the document node.</li>
				2670	</ol>
				2671
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2672	<p>Ok then what happens when saving the document (assuming you
				2673	collected/built an xmlDoc DOM like structure) ? It depends on the function
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2674	called, xmlSaveFile() will just try to save in the original encoding, while
				2675	xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
				2676	encoding:</p>
				2677	<ol>
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2678	<li>if no encoding is given, libxml2 will look for an encoding value
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2679	associated to the document and if it exists will try to save to that
				2680	encoding,
				2681	<p>otherwise everything is written in the internal form, i.e. UTF-8</p>
				2682	</li>
				2683	<li>so if an encoding was specified, either at the API level or on the
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2684	document, libxml2 will again canonicalize the encoding name, lookup for a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2685	converter in the registered set or through iconv. If not found the
				2686	function will return an error code</li>
				2687	<li>the converter is placed before the I/O buffer layer, as another kind of
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2688	buffer, then libxml2 will simply push the UTF-8 serialization to through
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2689	that buffer, which will then progressively be converted and pushed onto
				2690	the I/O layer.</li>
				2691	<li>It is possible that the converter code fails on some input, for example
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2692	trying to push an UTF-8 encoded Chinese character through the UTF-8 to
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2693	ISO-8859-1 converter won't work. Since the encoders are progressive they
				2694	will just report the error and the number of bytes converted, at that
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2695	point libxml2 will decode the offending character, remove it from the
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2696	buffer and replace it with the associated charRef encoding &#123; and
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2697	resume the conversion. This guarantees that any document will be saved
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2698	without losses (except for markup names where this is not legal, this is
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2699	a problem in the current version, in practice avoid using non-ascii
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2700	characters for tags or attributes names @@). A special "ascii" encoding
				2701	name is used to save documents to a pure ascii form can be used when
				2702	portability is really crucial</li>
				2703	</ol>
				2704
				2705	<p>Here is a few examples based on the same test document:</p>
				2706	<pre>~/XML -> ./xmllint isolat1
				2707	<?xml version="1.0" encoding="ISO-8859-1"?>
				2708	<très>là</très>
				2709	~/XML -> ./xmllint --encode UTF-8 isolat1
				2710	<?xml version="1.0" encoding="UTF-8"?>
				2711	<trÃ¨s>lÃ </trÃ¨s>
				2712	~/XML -> </pre>
				2713
				2714	<p>The same processing is applied (and reuse most of the code) for HTML I18N
				2715	processing. Looking up and modifying the content encoding is a bit more
				2716	difficult since it is located in a <meta> tag under the <head>,
				2717	so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
				2718	been provided. The parser also attempts to switch encoding on the fly when
				2719	detecting such a tag on input. Except for that the processing is the same
				2720	(and again reuses the same code).</p>
				2721
				2722	<h3><a name="Default">Default supported encodings</a></h3>
				2723
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2724	<p>libxml2 has a set of default converters for the following encodings
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2725	(located in encoding.c):</p>
				2726	<ol>
				2727	<li>UTF-8 is supported by default (null handlers)</li>
				2728	<li>UTF-16, both little and big endian</li>
				2729	<li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
				2730	<li>ASCII, useful mostly for saving</li>
				2731	<li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
				2732	predefined entities like &copy; for the Copyright sign.</li>
				2733	</ol>
				2734
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2735	<p>More over when compiled on an Unix platform with iconv support the full
				2736	set of encodings supported by iconv can be instantly be used by libxml. On a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2737	linux machine with glibc-2.1 the list of supported encodings and aliases fill
				2738	3 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
				2739	various Japanese ones.</p>
				2740
				2741	<h4>Encoding aliases</h4>
				2742
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2743	<p>From 2.2.3, libxml2 has support to register encoding names aliases. The
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2744	goal is to be able to parse document whose encoding is supported but where
				2745	the name differs (for example from the default set of names accepted by
				2746	iconv). The following functions allow to register and handle new aliases for
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2747	existing encodings. Once registered libxml2 will automatically lookup the
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2748	aliases when handling a document:</p>
				2749	<ul>
				2750	<li>int xmlAddEncodingAlias(const char name, const char alias);</li>
				2751	<li>int xmlDelEncodingAlias(const char *alias);</li>
				2752	<li>const char * xmlGetEncodingAlias(const char *alias);</li>
				2753	<li>void xmlCleanupEncodingAliases(void);</li>
				2754	</ul>
				2755
				2756	<h3><a name="extend">How to extend the existing support</a></h3>
				2757
				2758	<p>Well adding support for new encoding, or overriding one of the encoders
				2759	(assuming it is buggy) should not be hard, just write an input and output
				2760	conversion routines to/from UTF-8, and register them using
				2761	xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
				2762	called automatically if the parser(s) encounter such an encoding name
				2763	(register it uppercase, this will help). The description of the encoders,
				2764	their arguments and expected return values are described in the encoding.h
				2765	header.</p>
				2766
				2767	<p>A quick note on the topic of subverting the parser to use a different
				2768	internal encoding than UTF-8, in some case people will absolutely want to
				2769	keep the internal encoding different, I think it's still possible (but the
				2770	encoding must be compliant with ASCII on the same subrange) though I didn't
				2771	tried it. The key is to override the default conversion routines (by
				2772	registering null encoders/decoders for your charsets), and bypass the UTF-8
				2773	checking of the parser by setting the parser context charset
				2774	(ctxt->charset) to something different than XML_CHAR_ENCODING_UTF8, but
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2775	there is no guarantee that this will work. You may also have some troubles
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2776	saving back.</p>
				2777
				2778	<p>Basically proper I18N support is important, this requires at least
				2779	libxml-2.0.0, but a lot of features and corrections are really available only
				2780	starting 2.2.</p>
				2781
				2782	<h2><a name="IO">I/O Interfaces</a></h2>
				2783
				2784	<p>Table of Content:</p>
				2785	<ol>
				2786	<li><a href="#General1">General overview</a></li>
				2787	<li><a href="#basic">The basic buffer type</a></li>
				2788	<li><a href="#Input">Input I/O handlers</a></li>
				2789	<li><a href="#Output">Output I/O handlers</a></li>
				2790	<li><a href="#entities">The entities loader</a></li>
				2791	<li><a href="#Example2">Example of customized I/O</a></li>
				2792	</ol>
				2793
				2794	<h3><a name="General1">General overview</a></h3>
				2795
				2796	<p>The module <code><a
				2797	href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2798	the interfaces to the libxml2 I/O system. This consists of 4 main parts:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2799	<ul>
				2800	<li>Entities loader, this is a routine which tries to fetch the entities
				2801	(files) based on their PUBLIC and SYSTEM identifiers. The default loader
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2802	don't look at the public identifier since libxml2 do not maintain a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2803	catalog. You can redefine you own entity loader by using
				2804	<code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	2805	<code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
				2806	example</a>.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2807	<li>Input I/O buffers which are a commodity structure used by the parser(s)
				2808	input layer to handle fetching the informations to feed the parser. This
				2809	provides buffering and is also a placeholder where the encoding
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2810	converters to UTF8 are piggy-backed.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2811	<li>Output I/O buffers are similar to the Input ones and fulfill similar
				2812	task but when generating a serialization from a tree.</li>
				2813	<li>A mechanism to register sets of I/O callbacks and associate them with
				2814	specific naming schemes like the protocol part of the URIs.
				2815	<p>This affect the default I/O operations and allows to use specific I/O
				2816	handlers for certain names.</p>
				2817	</li>
				2818	</ul>
				2819
				2820	<p>The general mechanism used when loading http://rpmfind.net/xml.html for
				2821	example in the HTML parser is the following:</p>
				2822	<ol>
				2823	<li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
				2824	the parsing context and the URI string.</li>
				2825	<li>the URI string is checked against the existing registered handlers
				2826	using their match() callback function, if the HTTP module was compiled
				2827	in, it is registered and its match() function will succeeds</li>
				2828	<li>the open() function of the handler is called and if successful will
				2829	return an I/O Input buffer</li>
				2830	<li>the parser will the start reading from this buffer and progressively
				2831	fetch information from the resource, calling the read() function of the
				2832	handler until the resource is exhausted</li>
				2833	<li>if an encoding change is detected it will be installed on the input
				2834	buffer, providing buffering and efficient use of the conversion
				2835	routines</li>
				2836	<li>once the parser has finished, the close() function of the handler is
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2837	called once and the Input buffer and associated resources are
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2838	deallocated.</li>
				2839	</ol>
				2840
				2841	<p>The user defined callbacks are checked first to allow overriding of the
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	2842	default libxml2 I/O routines.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2843
				2844	<h3><a name="basic">The basic buffer type</a></h3>
				2845
				2846	<p>All the buffer manipulation handling is done using the
				2847	<code>xmlBuffer</code> type define in <code><a
				2848	href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
				2849	resizable memory buffer. The buffer allocation strategy can be selected to be
				2850	either best-fit or use an exponential doubling one (CPU vs. memory use
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2851	trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2852	<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
				2853	system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
				2854	of functions allows to manipulate buffers with names starting with the
				2855	<code>xmlBuffer...</code> prefix.</p>
				2856
				2857	<h3><a name="Input">Input I/O handlers</a></h3>
				2858
				2859	<p>An Input I/O handler is a simple structure
				2860	<code>xmlParserInputBuffer</code> containing a context associated to the
				2861	resource (file descriptor, or pointer to a protocol handler), the read() and
				2862	close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
				2863	encoding handler are also present to support charset conversion when
				2864	needed.</p>
				2865
				2866	<h3><a name="Output">Output I/O handlers</a></h3>
				2867
				2868	<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
				2869	Input one except the callbacks are write() and close().</p>
				2870
				2871	<h3><a name="entities">The entities loader</a></h3>
				2872
				2873	<p>The entity loader resolves requests for new entities and create inputs for
				2874	the parser. Creating an input from a filename or an URI string is done
				2875	through the xmlNewInputFromFile() routine. The default entity loader do not
				2876	handle the PUBLIC identifier associated with an entity (if any). So it just
				2877	calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
				2878	XML).</p>
				2879
				2880	<p>If you want to hook up a catalog mechanism then you simply need to
				2881	override the default entity loader, here is an example:</p>
				2882	<pre>#include <libxml/xmlIO.h>
				2883
				2884	xmlExternalEntityLoader defaultLoader = NULL;
				2885
				2886	xmlParserInputPtr
				2887	xmlMyExternalEntityLoader(const char URL, const char ID,
				2888	xmlParserCtxtPtr ctxt) {
				2889	xmlParserInputPtr ret;
				2890	const char *fileID = NULL;
				2891	/* lookup for the fileID depending on ID */
				2892
				2893	ret = xmlNewInputFromFile(ctxt, fileID);
				2894	if (ret != NULL)
				2895	return(ret);
				2896	if (defaultLoader != NULL)
				2897	ret = defaultLoader(URL, ID, ctxt);
				2898	return(ret);
				2899	}
				2900
				2901	int main(..) {
				2902	...
				2903
				2904	/*
				2905	* Install our own entity loader
				2906	*/
				2907	defaultLoader = xmlGetExternalEntityLoader();
				2908	xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
				2909
				2910	...
				2911	}</pre>
				2912
				2913	<h3><a name="Example2">Example of customized I/O</a></h3>
				2914
				2915	<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
				2916	real use case</a>, xmlDocDump() closes the FILE * passed by the application
				2917	and this was a problem. The <a
				2918	href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
				2919	new output handler with the closing call deactivated:</p>
				2920	<ol>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2921	<li>First define a new I/O output allocator where the output don't close
				2922	the file:
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2923	<pre>xmlOutputBufferPtr
				2924	xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
				2925	xmlOutputBufferPtr ret;
				2926
				2927	if (xmlOutputCallbackInitialized == 0)
				2928	xmlRegisterDefaultOutputCallbacks();
				2929
				2930	if (file == NULL) return(NULL);
				2931	ret = xmlAllocOutputBuffer(encoder);
				2932	if (ret != NULL) {
				2933	ret->context = file;
				2934	ret->writecallback = xmlFileWrite;
				2935	ret->closecallback = NULL; /* No close callback */
				2936	}
Daniel Veillard	f83a2c7	2003-04-08 13:48:40 +0000	[diff] [blame]	2937	return(ret);
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2938	} </pre>
				2939	</li>
				2940	<li>And then use it to save the document:
				2941	<pre>FILE *f;
				2942	xmlOutputBufferPtr output;
				2943	xmlDocPtr doc;
				2944	int res;
				2945
				2946	f = ...
				2947	doc = ....
				2948
				2949	output = xmlOutputBufferCreateOwn(f, NULL);
				2950	res = xmlSaveFileTo(output, doc, NULL);
				2951	</pre>
				2952	</li>
				2953	</ol>
				2954
				2955	<h2><a name="Catalog">Catalog support</a></h2>
				2956
				2957	<p>Table of Content:</p>
				2958	<ol>
				2959	<li><a href="General2">General overview</a></li>
				2960	<li><a href="#definition">The definition</a></li>
				2961	<li><a href="#Simple">Using catalogs</a></li>
				2962	<li><a href="#Some">Some examples</a></li>
				2963	<li><a href="#reference">How to tune catalog usage</a></li>
				2964	<li><a href="#validate">How to debug catalog processing</a></li>
				2965	<li><a href="#Declaring">How to create and maintain catalogs</a></li>
				2966	<li><a href="#implemento">The implementor corner quick review of the
				2967	API</a></li>
				2968	<li><a href="#Other">Other resources</a></li>
				2969	</ol>
				2970
				2971	<h3><a name="General2">General overview</a></h3>
				2972
				2973	<p>What is a catalog? Basically it's a lookup mechanism used when an entity
				2974	(a file or a remote resource) references another entity. The catalog lookup
				2975	is inserted between the moment the reference is recognized by the software
				2976	(XML parser, stylesheet processing, or even images referenced for inclusion
				2977	in a rendering) and the time where loading that resource is actually
				2978	started.</p>
				2979
				2980	<p>It is basically used for 3 things:</p>
				2981	<ul>
				2982	<li>mapping from "logical" names, the public identifiers and a more
				2983	concrete name usable for download (and URI). For example it can associate
				2984	the logical name
				2985	<p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
				2986	<p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
				2987	downloaded</p>
				2988	<p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
				2989	</li>
				2990	<li>remapping from a given URL to another one, like an HTTP indirection
				2991	saying that
				2992	<p>"http://www.oasis-open.org/committes/tr.xsl"</p>
				2993	<p>should really be looked at</p>
				2994	<p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
				2995	</li>
				2996	<li>providing a local cache mechanism allowing to load the entities
				2997	associated to public identifiers or remote resources, this is a really
				2998	important feature for any significant deployment of XML or SGML since it
				2999	allows to avoid the aleas and delays associated to fetching remote
				3000	resources.</li>
				3001	</ul>
				3002
				3003	<h3><a name="definition">The definitions</a></h3>
				3004
				3005	<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
				3006	<ul>
				3007	<li>the older SGML catalogs, the official spec is SGML Open Technical
				3008	Resolution TR9401:1997, but is better understood by reading <a
				3009	href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
				3010	James Clark. This is relatively old and not the preferred mode of
				3011	operation of libxml.</li>
				3012	<li><a href="http://www.oasis-open.org/committees/entity/spec.html">XML
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	3013	Catalogs</a> is far more flexible, more recent, uses an XML syntax and
				3014	should scale quite better. This is the default option of libxml.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3015	</ul>
				3016
				3017	<p></p>
				3018
				3019	<h3><a name="Simple">Using catalog</a></h3>
				3020
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3021	<p>In a normal environment libxml2 will by default check the presence of a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3022	catalog in /etc/xml/catalog, and assuming it has been correctly populated,
				3023	the processing is completely transparent to the document user. To take a
				3024	concrete example, suppose you are authoring a DocBook document, this one
				3025	starts with the following DOCTYPE definition:</p>
				3026	<pre><?xml version='1.0'?>
				3027	<!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
				3028	"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"></pre>
				3029
				3030	<p>When validating the document with libxml, the catalog will be
				3031	automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
				3032	DocBk XML V3.1.4//EN" and the system identifier
				3033	"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
				3034	been installed on your system and the catalogs actually point to them, libxml
				3035	will fetch them from the local disk.</p>
				3036
				3037	<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
				3038	DOCTYPE example it's a really old version, but is fine as an example.</p>
				3039
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3040	<p>Libxml2 will check the catalog each time that it is requested to load an
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3041	entity, this includes DTD, external parsed entities, stylesheets, etc ... If
				3042	your system is correctly configured all the authoring phase and processing
				3043	should use only local files, even if your document stays portable because it
				3044	uses the canonical public and system ID, referencing the remote document.</p>
				3045
				3046	<h3><a name="Some">Some examples:</a></h3>
				3047
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3048	<p>Here is a couple of fragments from XML Catalogs used in libxml2 early
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3049	regression tests in <code>test/catalogs</code> :</p>
				3050	<pre><?xml version="1.0"?>
				3051	<!DOCTYPE catalog PUBLIC
				3052	"-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3053	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3054	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
				3055	<public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
				3056	uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
				3057	...</pre>
				3058
				3059	<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
				3060	written in XML, there is a specific namespace for catalog elements
				3061	"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
				3062	catalog is a <code>public</code> mapping it allows to associate a Public
				3063	Identifier with an URI.</p>
				3064	<pre>...
				3065	<rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
				3066	rewritePrefix="file:///usr/share/xml/docbook/"/>
				3067	...</pre>
				3068
				3069	<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
				3070	any URI starting with a given prefix should be looked at another URI
				3071	constructed by replacing the prefix with an new one. In effect this acts like
				3072	a cache system for a full area of the Web. In practice it is extremely useful
				3073	with a file prefix if you have installed a copy of those resources on your
				3074	local system.</p>
				3075	<pre>...
				3076	<delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
				3077	catalog="file:///usr/share/xml/docbook.xml"/>
				3078	<delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
				3079	catalog="file:///usr/share/xml/docbook.xml"/>
				3080	<delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
				3081	catalog="file:///usr/share/xml/docbook.xml"/>
				3082	<delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
				3083	catalog="file:///usr/share/xml/docbook.xml"/>
				3084	<delegateURI uriStartString="http://www.oasis-open.org/docbook/"
				3085	catalog="file:///usr/share/xml/docbook.xml"/>
				3086	...</pre>
				3087
				3088	<p>Delegation is the core features which allows to build a tree of catalogs,
				3089	easier to maintain than a single catalog, based on Public Identifier, System
				3090	Identifier or URI prefixes it instructs the catalog software to look up
				3091	entries in another resource. This feature allow to build hierarchies of
				3092	catalogs, the set of entries presented should be sufficient to redirect the
				3093	resolution of all DocBook references to the specific catalog in
				3094	<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
				3095	references for DocBook 4.2.1 to a specific catalog installed at the same time
				3096	as the DocBook resources on the local machine.</p>
				3097
				3098	<h3><a name="reference">How to tune catalog usage:</a></h3>
				3099
				3100	<p>The user can change the default catalog behaviour by redirecting queries
				3101	to its own set of catalogs, this can be done by setting the
				3102	<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
				3103	empty one should deactivate loading the default <code>/etc/xml/catalog</code>
				3104	default catalog</p>
				3105
				3106	<h3><a name="validate">How to debug catalog processing:</a></h3>
				3107
				3108	<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3109	make libxml2 output debugging informations for each catalog operations, for
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3110	example:</p>
				3111	<pre>orchis:~/XML -> xmllint --memory --noout test/ent2
				3112	warning: failed to load external entity "title.xml"
				3113	orchis:~/XML -> export XML_DEBUG_CATALOG=
				3114	orchis:~/XML -> xmllint --memory --noout test/ent2
				3115	Failed to parse catalog /etc/xml/catalog
				3116	Failed to parse catalog /etc/xml/catalog
				3117	warning: failed to load external entity "title.xml"
				3118	Catalogs cleanup
				3119	orchis:~/XML -> </pre>
				3120
				3121	<p>The test/ent2 references an entity, running the parser from memory makes
				3122	the base URI unavailable and the the "title.xml" entity cannot be loaded.
				3123	Setting up the debug environment variable allows to detect that an attempt is
				3124	made to load the <code>/etc/xml/catalog</code> but since it's not present the
				3125	resolution fails.</p>
				3126
				3127	<p>But the most advanced way to debug XML catalog processing is to use the
				3128	<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
				3129	catalogs and make resolution queries to see what is going on. This is also
				3130	used for the regression tests:</p>
				3131	<pre>orchis:~/XML -> ./xmlcatalog test/catalogs/docbook.xml \
				3132	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3133	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3134	orchis:~/XML -> </pre>
				3135
				3136	<p>For debugging what is going on, adding one -v flags increase the verbosity
				3137	level to indicate the processing done (adding a second flag also indicate
				3138	what elements are recognized at parsing):</p>
				3139	<pre>orchis:~/XML -> ./xmlcatalog -v test/catalogs/docbook.xml \
				3140	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3141	Parsing catalog test/catalogs/docbook.xml's content
				3142	Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
				3143	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3144	Catalogs cleanup
				3145	orchis:~/XML -> </pre>
				3146
				3147	<p>A shell interface is also available to debug and process multiple queries
				3148	(and for regression tests):</p>
				3149	<pre>orchis:~/XML -> ./xmlcatalog -shell test/catalogs/docbook.xml \
				3150	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3151	> help
				3152	Commands available:
				3153	public PublicID: make a PUBLIC identifier lookup
				3154	system SystemID: make a SYSTEM identifier lookup
				3155	resolve PublicID SystemID: do a full resolver lookup
				3156	add 'type' 'orig' 'replace' : add an entry
				3157	del 'values' : remove values
				3158	dump: print the current catalog state
				3159	debug: increase the verbosity level
				3160	quiet: decrease the verbosity level
				3161	exit: quit the shell
				3162	> public "-//OASIS//DTD DocBook XML V4.1.2//EN"
				3163	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3164	> quit
				3165	orchis:~/XML -> </pre>
				3166
				3167	<p>This should be sufficient for most debugging purpose, this was actually
				3168	used heavily to debug the XML Catalog implementation itself.</p>
				3169
				3170	<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
				3171
				3172	<p>Basically XML Catalogs are XML files, you can either use XML tools to
				3173	manage them or use <strong>xmlcatalog</strong> for this. The basic step is
				3174	to create a catalog the -create option provide this facility:</p>
				3175	<pre>orchis:~/XML -> ./xmlcatalog --create tst.xml
				3176	<?xml version="1.0"?>
				3177	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3178	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3179	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
				3180	orchis:~/XML -> </pre>
				3181
				3182	<p>By default xmlcatalog does not overwrite the original catalog and save the
				3183	result on the standard output, this can be overridden using the -noout
				3184	option. The <code>-add</code> command allows to add entries in the
				3185	catalog:</p>
				3186	<pre>orchis:~/XML -> ./xmlcatalog --noout --create --add "public" \
				3187	"-//OASIS//DTD DocBook XML V4.1.2//EN" \
				3188	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
				3189	orchis:~/XML -> cat tst.xml
				3190	<?xml version="1.0"?>
				3191	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
				3192	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3193	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
				3194	<public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
				3195	uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
				3196	</catalog>
				3197	orchis:~/XML -> </pre>
				3198
				3199	<p>The <code>-add</code> option will always take 3 parameters even if some of
				3200	the XML Catalog constructs (like nextCatalog) will have only a single
				3201	argument, just pass a third empty string, it will be ignored.</p>
				3202
				3203	<p>Similarly the <code>-del</code> option remove matching entries from the
				3204	catalog:</p>
				3205	<pre>orchis:~/XML -> ./xmlcatalog --del \
				3206	"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
				3207	<?xml version="1.0"?>
				3208	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3209	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3210	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
				3211	orchis:~/XML -> </pre>
				3212
				3213	<p>The catalog is now empty. Note that the matching of <code>-del</code> is
				3214	exact and would have worked in a similar fashion with the Public ID
				3215	string.</p>
				3216
				3217	<p>This is rudimentary but should be sufficient to manage a not too complex
				3218	catalog tree of resources.</p>
				3219
				3220	<h3><a name="implemento">The implementor corner quick review of the
				3221	API:</a></h3>
				3222
				3223	<p>First, and like for every other module of libxml, there is an
				3224	automatically generated <a href="html/libxml-catalog.html">API page for
				3225	catalog support</a>.</p>
				3226
				3227	<p>The header for the catalog interfaces should be included as:</p>
				3228	<pre>#include <libxml/catalog.h></pre>
				3229
				3230	<p>The API is voluntarily kept very simple. First it is not obvious that
				3231	applications really need access to it since it is the default behaviour of
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3232	libxml2 (Note: it is possible to completely override libxml2 default catalog by
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3233	using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
				3234	plug an application specific resolver).</p>
				3235
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3236	<p>Basically libxml2 support 2 catalog lists:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3237	<ul>
				3238	<li>the default one, global shared by all the application</li>
				3239	<li>a per-document catalog, this one is built if the document uses the
				3240	<code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
				3241	associated to the parser context and destroyed when the parsing context
				3242	is destroyed.</li>
				3243	</ul>
				3244
				3245	<p>the document one will be used first if it exists.</p>
				3246
				3247	<h4>Initialization routines:</h4>
				3248
				3249	<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
				3250	used at startup to initialize the catalog, if the catalog should be
				3251	initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
				3252	should be called before xmlInitializeCatalog() which would otherwise do a
				3253	default initialization first.</p>
				3254
				3255	<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
				3256	own catalog list if needed.</p>
				3257
				3258	<h4>Preferences setup:</h4>
				3259
				3260	<p>The XML Catalog spec requires the possibility to select default
				3261	preferences between public and system delegation,
				3262	xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
				3263	xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
				3264	be forbidden, allowed for global catalog, for document catalog or both, the
				3265	default is to allow both.</p>
				3266
				3267	<p>And of course xmlCatalogSetDebug() allows to generate debug messages
				3268	(through the xmlGenericError() mechanism).</p>
				3269
				3270	<h4>Querying routines:</h4>
				3271
				3272	<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
				3273	and xmlCatalogResolveURI() are relatively explicit if you read the XML
				3274	Catalog specification they correspond to section 7 algorithms, they should
				3275	also work if you have loaded an SGML catalog with a simplified semantic.</p>
				3276
				3277	<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
				3278	operate on the document catalog list</p>
				3279
				3280	<h4>Cleanup and Miscellaneous:</h4>
				3281
				3282	<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
				3283	the per-document equivalent.</p>
				3284
				3285	<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
				3286	first catalog in the global list, and xmlCatalogDump() allows to dump a
				3287	catalog state, those routines are primarily designed for xmlcatalog, I'm not
				3288	sure that exposing more complex interfaces (like navigation ones) would be
				3289	really useful.</p>
				3290
				3291	<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
				3292	it's similar as xmlParseFile() except it bypass all catalog lookups, it's
				3293	provided because this functionality may be useful for client tools.</p>
				3294
				3295	<h4>threaded environments:</h4>
				3296
				3297	<p>Since the catalog tree is built progressively, some care has been taken to
				3298	try to avoid troubles in multithreaded environments. The code is now thread
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3299	safe assuming that the libxml2 library has been compiled with threads
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3300	support.</p>
				3301
				3302	<p></p>
				3303
				3304	<h3><a name="Other">Other resources</a></h3>
				3305
				3306	<p>The XML Catalog specification is relatively recent so there isn't much
				3307	literature to point at:</p>
				3308	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3309	<li>You can find a good rant from Norm Walsh about <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3310	href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
				3311	need for catalogs</a>, it provides a lot of context informations even if
Daniel Veillard	93d3a47	2002-04-26 14:04:55 +0000	[diff] [blame]	3312	I don't agree with everything presented. Norm also wrote a more recent
				3313	article <a
				3314	href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
				3315	entities and URI resolvers</a> describing them.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3316	<li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
				3317	catalog proposal</a> from John Cowan</li>
				3318	<li>The <a href="http://www.rddl.org/">Resource Directory Description
				3319	Language</a> (RDDL) another catalog system but more oriented toward
				3320	providing metadata for XML namespaces.</li>
				3321	<li>the page from the OASIS Technical <a
				3322	href="http://www.oasis-open.org/committees/entity/">Committee on Entity
				3323	Resolution</a> who maintains XML Catalog, you will find pointers to the
				3324	specification update, some background and pointers to others tools
				3325	providing XML Catalog support</li>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3326	<li>Here is a <a href="buildDocBookCatalog">shell script</a> to generate
				3327	XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
				3328	directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
				3329	the resources found on the system. Otherwise it will just create
				3330	~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillard	8594de9	2003-04-25 10:08:44 +0000	[diff] [blame]	3331	<p><code>export XML_CATALOG_FILES=$HOME/xmlcatalog</code></p>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3332	<p>should allow to process DocBook documentations without requiring
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3333	network accesses for the DTD or stylesheets</p>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3334	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3335	<li>I have uploaded <a href="ftp://xmlsoft.org/test/dbk412catalog.tar.gz">a
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3336	small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
				3337	to work fine for me too</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3338	<li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
				3339	manual page</a></li>
				3340	</ul>
				3341
				3342	<p>If you have suggestions for corrections or additions, simply contact
				3343	me:</p>
				3344
				3345	<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3346
				3347	<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3348	using the XML tollkit from the C language. It is not intended to be
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3349	extensive. I hope the automatically generated documents will provide the
				3350	completeness required, but as a separate set of documents. The interfaces of
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3351	the XML parser are by principle low level,
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3352	Those interested in a higher level API should <a href="#DOM">look at
				3353	DOM</a>.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	3354
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3355	<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
				3356	separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3357	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]	3358
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3359	<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3360
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3361	<p>Usually, the first thing to do is to read an XML input. The parser accepts
				3362	documents either from in-memory strings or from files. The functions are
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3363	defined in "parser.h":</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3364	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3365	<dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3366	<dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3367	</dd>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3368	</dl>
				3369	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3370	<dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3371	<dd><p>Parse an XML document contained in a (possibly compressed)
				3372	file.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3373	</dd>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3374	</dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3375
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3376	<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]	3377	failure).</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3378
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3379	<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3380
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3381	<p>In order for the application to keep the control when the document is
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3382	being fetched (which is common for GUI based programs) libxml2 provides a push
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3383	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]	3384	<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
				3385	void *user_data,
				3386	const char *chunk,
				3387	int size,
				3388	const char *filename);
				3389	int xmlParseChunk (xmlParserCtxtPtr ctxt,
				3390	const char *chunk,
				3391	int size,
				3392	int terminate);</pre>
				3393
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3394	<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]	3395	<pre> FILE *f;
				3396
				3397	f = fopen(filename, "r");
				3398	if (f != NULL) {
				3399	int res, size = 1024;
				3400	char chars[1024];
				3401	xmlParserCtxtPtr ctxt;
				3402
				3403	res = fread(chars, 1, 4, f);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3404	if (res > 0) {
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3405	ctxt = xmlCreatePushParserCtxt(NULL, NULL,
				3406	chars, res, filename);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3407	while ((res = fread(chars, 1, size, f)) > 0) {
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3408	xmlParseChunk(ctxt, chars, res, 0);
				3409	}
				3410	xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3411	doc = ctxt->myDoc;
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3412	xmlFreeParserCtxt(ctxt);
				3413	}
				3414	}</pre>
				3415
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3416	<p>The HTML parser embedded into libxml2 also has a push interface; the
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3417	functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3418
				3419	<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
				3420
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3421	<p>The tree-building interface makes the parser memory-hungry, first loading
				3422	the document in memory and then building the tree itself. Reading a document
				3423	without building the tree is possible using the SAX interfaces (see SAX.h and
				3424	<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]	3425	Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3426	limited to SAX: just use the two first arguments of
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3427	<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	3428
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3429	<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3430
				3431	<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]	3432	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]	3433	also described in <libxml/tree.h>.) For example, here is a piece of
				3434	code that produces the XML document used in the previous examples:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3435	<pre> #include <libxml/tree.h>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	3436	xmlDocPtr doc;
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3437	xmlNodePtr tree, subtree;
				3438
				3439	doc = xmlNewDoc("1.0");
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3440	doc->children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
				3441	xmlSetProp(doc->children, "prop1", "gnome is great");
				3442	xmlSetProp(doc->children, "prop2", "& linux too");
				3443	tree = xmlNewChild(doc->children, NULL, "head", NULL);
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3444	subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3445	tree = xmlNewChild(doc->children, NULL, "chapter", NULL);
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3446	subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
				3447	subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
				3448	subtree = xmlNewChild(tree, NULL, "image", NULL);
				3449	xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3450
				3451	<p>Not really rocket science ...</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3452
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3453	<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3454
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3455	<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]	3456	code has access to the internal structure of all the elements of the tree.
				3457	The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	3458	<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3459	<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3460	example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3461	<pre><code>doc->children->children->children</code></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3462
				3463	<p>points to the title element,</p>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3464	<pre>doc->children->children->next->children->children</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3465
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3466	<p>points to the text node containing the chapter title "The Linux
				3467	adventure".</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3468
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	3469	<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]	3470	present before the document root, so <code>doc->children</code> may point
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3471	to an element which is not the document Root Element; a function
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	3472	<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	3473
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3474	<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3475
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3476	<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3477	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]	3478	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3479	<dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
				3480	xmlChar *value);</code></dt>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3481	<dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
				3482	The value can be NULL.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3483	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3484	</dl>
				3485	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3486	<dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3487	*name);</code></dt>
Daniel Veillard	c92c304	2000-09-29 02:42:04 +0000	[diff] [blame]	3488	<dd><p>This function returns a pointer to new copy of the property
				3489	content. Note that the user must deallocate the result.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3490	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3491	</dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3492
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3493	<p>Two functions are provided for reading and writing the text associated
				3494	with elements:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3495	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3496	<dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3497	*value);</code></dt>
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3498	<dd><p>This function takes an "external" string and converts it to one
				3499	text node or possibly to a list of entity and text nodes. All
				3500	non-predefined entity references like &Gnome; will be stored
				3501	internally as entity nodes, hence the result of the function may not be
				3502	a single node.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3503	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3504	</dl>
				3505	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3506	<dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3507	inLine);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3508	<dd><p>This function is the inverse of
				3509	<code>xmlStringGetNodeList()</code>. It generates a new string
				3510	containing the content of the text and entity nodes. Note the extra
				3511	argument inLine. If this argument is set to 1, the function will expand
				3512	entity references. For example, instead of returning the &Gnome;
				3513	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]	3514	"GNU Network Object Model Environment").</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3515	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3516	</dl>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3517
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3518	<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3519
				3520	<p>Basically 3 options are possible:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3521	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3522	<dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3523	*size);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3524	<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]	3525	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3526	</dl>
				3527	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3528	<dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3529	<dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3530	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3531	</dl>
				3532	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3533	<dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3534	<dd><p>Saves the document to a file. In this case, the compression
				3535	interface is triggered if it has been turned on.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3536	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3537	</dl>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3538
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3539	<h3><a name="Compressio">Compression</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3540
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3541	<p>The library transparently handles compression when doing file-based
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3542	accesses. The level of compression on saves can be turned on either globally
				3543	or individually for one file:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3544	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3545	<dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3546	<dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3547	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3548	</dl>
				3549	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3550	<dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3551	<dd><p>Sets the document compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3552	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3553	</dl>
				3554	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3555	<dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3556	<dd><p>Gets the default compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3557	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3558	</dl>
				3559	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3560	<dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3561	<dd><p>Sets the default compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3562	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3563	</dl>
				3564
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3565	<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3566
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3567	<p>Entities in principle are similar to simple C macros. An entity defines an
				3568	abbreviation for a given string that you can reuse many times throughout the
				3569	content of your document. Entities are especially useful when a given string
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3570	may occur frequently within a document, or to confine the change needed to a
				3571	document to a restricted area in the internal subset of the document (at the
				3572	beginning). Example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3573	<pre>1 <?xml version="1.0"?>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3574	2 <!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3575	3 <!ENTITY xml "Extensible Markup Language">
				3576	4 ]>
				3577	5 <EXAMPLE>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3578	6 &xml;
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3579	7 </EXAMPLE></pre>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3580
				3581	<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]	3582	its name with '&' and following it by ';' without any spaces added. There
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3583	are 5 predefined entities in libxml2 allowing you to escape characters with
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3584	predefined meaning in some parts of the xml document content:
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3585	<strong>&lt;</strong> for the character '<', <strong>&gt;</strong>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3586	for the character '>', <strong>&apos;</strong> for the character ''',
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3587	<strong>&quot;</strong> for the character '"', and
				3588	<strong>&amp;</strong> for the character '&'.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3589
				3590	<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]	3591	substitute an entity's content so that you can see the replacement text in
				3592	your application. Or you may prefer to keep entity references as such in the
				3593	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]	3594	precious information (if the user went through the pain of explicitly
				3595	defining entities, he may have a a rather negative attitude if you blindly
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3596	substitute them as saving time). The <a
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3597	href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3598	function allows you to check and change the behaviour, which is to not
				3599	substitute entities by default.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3600
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3601	<p>Here is the DOM tree built by libxml2 for the previous document in the
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3602	default case:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3603	<pre>/gnome/src/gnome-xml -> ./xmllint --debug test/ent1
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3604	DOCUMENT
				3605	version=1.0
				3606	ELEMENT EXAMPLE
				3607	TEXT
				3608	content=
				3609	ENTITY_REF
				3610	INTERNAL_GENERAL_ENTITY xml
				3611	content=Extensible Markup Language
				3612	TEXT
				3613	content=</pre>
				3614
				3615	<p>And here is the result when substituting entities:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3616	<pre>/gnome/src/gnome-xml -> ./tester --debug --noent test/ent1
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3617	DOCUMENT
				3618	version=1.0
				3619	ELEMENT EXAMPLE
				3620	TEXT
				3621	content= Extensible Markup Language</pre>
				3622
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3623	<p>So, entities or no entities? Basically, it depends on your use case. I
				3624	suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3625	entities in your XML document or data if you are not willing to handle the
				3626	entity references elements in the DOM tree.</p>
				3627
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3628	<p>Note that at save time libxml2 enforces the conversion of the predefined
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3629	entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3630	transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3631	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]	3632	finding them in the input).</p>
				3633
Daniel Veillard	7b9c4b7	2000-08-25 16:26:50 +0000	[diff] [blame]	3634	<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3635	on top of the libxml2 SAX interface is difficult!!! If you plan to use
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3636	non-predefined entities in your documents, then the learning curve to handle
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3637	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]	3638	strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard	8c6d6af	2000-08-25 17:14:13 +0000	[diff] [blame]	3639	deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard	7b9c4b7	2000-08-25 16:26:50 +0000	[diff] [blame]	3640
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3641	<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3642
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3643	<p>The libxml2 library implements <a
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3644	href="http://www.w3.org/TR/REC-xml-names/">XML namespaces</a> support by
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3645	recognizing namespace constructs in the input, and does namespace lookup
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3646	automatically when building the DOM tree. A namespace declaration is
				3647	associated with an in-memory structure and all elements or attributes within
				3648	that namespace point to it. Hence testing the namespace is a simple and fast
				3649	equality operation at the user level.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3650
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3651	<p>I suggest that people using libxml2 use a namespace, and declare it in the
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3652	root element of their document as the default namespace. Then they don't need
				3653	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]	3654	refinement and merging of data from different sources. This doesn't increase
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3655	the size of the XML output significantly, but significantly increases its
				3656	value in the long-term. Example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3657	<pre><mydoc xmlns="http://mydoc.example.org/schemas/">
				3658	<elem1>...</elem1>
				3659	<elem2>...</elem2>
				3660	</mydoc></pre>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3661
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3662	<p>The namespace value has to be an absolute URL, but the URL doesn't have to
				3663	point to any existing resource on the Web. It will bind all the element and
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	3664	attributes with that URL. I suggest to use an URL within a domain you
				3665	control, and that the URL should contain some kind of version information if
				3666	possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a
				3667	good namespace scheme.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3668
				3669	<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]	3670	version-independent prefix is installed on the root element of your document,
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3671	and if the version information don't match something you know, warn the user
				3672	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]	3673	namespace checking on the prefix value. <foo:text> may be exactly the
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3674	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]	3675	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]	3676	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]	3677	<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3678	prefix and its URI.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3679
				3680	<p>@@Interfaces@@</p>
				3681
				3682	<p>@@Examples@@</p>
				3683
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3684	<p>Usually people object to using namespaces together with validity checking.
				3685	I will try to make sure that using namespaces won't break validity checking,
				3686	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]	3687	suggest adding namespaces to your document. A default namespace scheme
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3688	<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3689	flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3690	from multiple DTDs will certainly break current validation schemes. I will
				3691	try to provide ways to do this, but this may not be portable or
				3692	standardized.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3693
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3694	<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3695
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3696	<p>Incompatible changes:</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3697
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3698	<p>Version 2 of libxml2 is the first version introducing serious backward
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3699	incompatible changes. The main goals were:</p>
				3700	<ul>
				3701	<li>a general cleanup. A number of mistakes inherited from the very early
				3702	versions couldn't be changed due to compatibility constraints. Example
				3703	the "childs" element in the nodes.</li>
				3704	<li>Uniformization of the various nodes, at least for their header and link
				3705	parts (doc, parent, children, prev, next), the goal is a simpler
				3706	programming model and simplifying the task of the DOM implementors.</li>
				3707	<li>better conformances to the XML specification, for example version 1.x
				3708	had an heuristic to try to detect ignorable white spaces. As a result the
				3709	SAX event generated were ignorableWhitespace() while the spec requires
				3710	character() in that case. This also mean that a number of DOM node
				3711	containing blank text may populate the DOM tree which were not present
				3712	before.</li>
				3713	</ul>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3714
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3715	<h3>How to fix libxml-1.x code:</h3>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3716
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3717	<p>So client code of libxml designed to run with version 1.x may have to be
				3718	changed to compile against version 2.x of libxml. Here is a list of changes
				3719	that I have collected, they may not be sufficient, so in case you find other
				3720	change which are required, <a href="mailto:Daniel.Ïeillardw3.org">drop me a
				3721	mail</a>:</p>
				3722	<ol>
				3723	<li>The package name have changed from libxml to libxml2, the library name
				3724	is now -lxml2 . There is a new xml2-config script which should be used to
				3725	select the right parameters libxml2</li>
				3726	<li>Node <strong>childs</strong> field has been renamed
				3727	<strong>children</strong> so s/childs/children/g should be applied
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3728	(probability of having "childs" anywhere else is close to 0+</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3729	<li>The document don't have anymore a <strong>root</strong> element it has
				3730	been replaced by <strong>children</strong> and usually you will get a
				3731	list of element here. For example a Dtd element for the internal subset
				3732	and it's declaration may be found in that list, as well as processing
				3733	instructions or comments found before or after the document root element.
				3734	Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3735	a document. Alternatively if you are sure to not reference DTDs nor have
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3736	PIs or comments before or after the root element
				3737	s/->root/->children/g will probably do it.</li>
				3738	<li>The white space issue, this one is more complex, unless special case of
				3739	validating parsing, the line breaks and spaces usually used for indenting
				3740	and formatting the document content becomes significant. So they are
				3741	reported by SAX and if your using the DOM tree, corresponding nodes are
				3742	generated. Too approach can be taken:
				3743	<ol>
				3744	<li>lazy one, use the compatibility call
				3745	<strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
				3746	relying on a special (and possibly broken) set of heuristics of
				3747	libxml to detect ignorable blanks. Don't complain if it breaks or
				3748	make your application not 100% clean w.r.t. to it's input.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3749	<li>the Right Way: change you code to accept possibly insignificant
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3750	blanks characters, or have your tree populated with weird blank text
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3751	nodes. You can spot them using the commodity function
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3752	<strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
				3753	nodes.</li>
				3754	</ol>
				3755	<p>Note also that with the new default the output functions don't add any
				3756	extra indentation when saving a tree in order to be able to round trip
				3757	(read and save) without inflating the document with extra formatting
				3758	chars.</p>
				3759	</li>
				3760	<li>The include path has changed to $prefix/libxml/ and the includes
				3761	themselves uses this new prefix in includes instructions... If you are
				3762	using (as expected) the
				3763	<pre>xml2-config --cflags</pre>
				3764	<p>output to generate you compile commands this will probably work out of
				3765	the box</p>
				3766	</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3767	<li>xmlDetectCharEncoding takes an extra argument indicating the length in
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3768	byte of the head of the document available for character detection.</li>
				3769	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3770
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3771	<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3772
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3773	<p>Two new version of libxml (1.8.11) and libxml2 (2.3.4) have been released
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3774	to allow smooth upgrade of existing libxml v1code while retaining
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3775	compatibility. They offers the following:</p>
				3776	<ol>
				3777	<li>similar include naming, one should use
				3778	<strong>#include<libxml/...></strong> in both cases.</li>
				3779	<li>similar identifiers defined via macros for the child and root fields:
				3780	respectively <strong>xmlChildrenNode</strong> and
				3781	<strong>xmlRootNode</strong></li>
				3782	<li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
				3783	inserted once in the client code</li>
				3784	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3785
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3786	<p>So the roadmap to upgrade your existing libxml applications is the
				3787	following:</p>
				3788	<ol>
				3789	<li>install the libxml-1.8.8 (and libxml-devel-1.8.8) packages</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3790	<li>find all occurrences where the xmlDoc <strong>root</strong> field is
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3791	used and change it to <strong>xmlRootNode</strong></li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	3792	<li>similarly find all occurrences where the xmlNode
				3793	<strong>childs</strong> field is used and change it to
				3794	<strong>xmlChildrenNode</strong></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3795	<li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
				3796	<strong>main()</strong> or in the library init entry point</li>
				3797	<li>Recompile, check compatibility, it should still work</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	3798	<li>Change your configure script to look first for xml2-config and fall
				3799	back using xml-config . Use the --cflags and --libs output of the command
				3800	as the Include and Linking parameters needed to use libxml.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3801	<li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
				3802	libxml-devel-1.8.y can be kept simultaneously)</li>
				3803	<li>remove your config.cache, relaunch your configuration mechanism, and
				3804	recompile, if steps 2 and 3 were done right it should compile as-is</li>
				3805	<li>Test that your application is still running correctly, if not this may
				3806	be due to extra empty nodes due to formating spaces being kept in libxml2
				3807	contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
				3808	code before calling the parser (next to
				3809	<strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
				3810	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3811
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3812	<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]	3813
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3814	<p>Let me put some emphasis on the fact that there is far more changes from
				3815	libxml 1.x to 2.x than the ones you may have to patch for. The overall code
				3816	has been considerably cleaned up and the conformance to the XML specification
				3817	has been drastically improved too. Don't take those changes as an excuse to
				3818	not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3819
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	3820	<h2><a name="Thread">Thread safety</a></h2>
				3821
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3822	<p>Starting with 2.4.7, libxml2 makes provisions to ensure that concurrent
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	3823	threads can safely work in parallel parsing different documents. There is
				3824	however a couple of things to do to ensure it:</p>
				3825	<ul>
				3826	<li>configure the library accordingly using the --with-threads options</li>
				3827	<li>call xmlInitParser() in the "main" thread before using any of the
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3828	libxml2 API (except possibly selecting a different memory allocator)</li>
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	3829	</ul>
				3830
				3831	<p>Note that the thread safety cannot be ensured for multiple threads sharing
				3832	the same document, the locking must be done at the application level, libxml
				3833	exports a basic mutex and reentrant mutexes API in <libxml/threads.h>.
				3834	The parts of the library checked for thread safety are:</p>
				3835	<ul>
				3836	<li>concurrent loading</li>
				3837	<li>file access resolution</li>
				3838	<li>catalog access</li>
				3839	<li>catalog building</li>
				3840	<li>entities lookup/accesses</li>
				3841	<li>validation</li>
				3842	<li>global variables per-thread override</li>
				3843	<li>memory handling</li>
				3844	</ul>
				3845
				3846	<p>XPath is supposed to be thread safe now, but this wasn't tested
				3847	seriously.</p>
				3848
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	3849	<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3850
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3851	<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
				3852	Object Model</em>; this is an API for accessing XML or HTML structured
				3853	documents. Native support for DOM in Gnome is on the way (module gnome-dom),
				3854	and will be based on gnome-xml. This will be a far cleaner interface to
				3855	manipulate XML files within Gnome since it won't expose the internal
				3856	structure.</p>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3857
Daniel Veillard	8a46917	2003-06-12 16:05:07 +0000	[diff] [blame^]	3858	<p>The current DOM implementation on top of libxml2 is the <a
Daniel Veillard	a47fb3d	2001-03-25 17:23:49 +0000	[diff] [blame]	3859	href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
				3860	is a full DOM interface, thanks to Paolo Casarini, check the <a
				3861	href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
				3862	informations.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3863
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	3864	<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]	3865
				3866	<p>Here is a real size example, where the actual content of the application
				3867	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]	3868	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]	3869	storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
				3870	base</a>:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3871	<pre><?xml version="1.0"?>
				3872	<gjob:Helping xmlns:gjob="http://www.gnome.org/some-location">
				3873	<gjob:Jobs>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3874
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3875	<gjob:Job>
				3876	<gjob:Project ID="3"/>
				3877	<gjob:Application>GBackup</gjob:Application>
				3878	<gjob:Category>Development</gjob:Category>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3879
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3880	<gjob:Update>
				3881	<gjob:Status>Open</gjob:Status>
				3882	<gjob:Modified>Mon, 07 Jun 1999 20:27:45 -0400 MET DST</gjob:Modified>
				3883	<gjob:Salary>USD 0.00</gjob:Salary>
				3884	</gjob:Update>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3885
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3886	<gjob:Developers>
				3887	<gjob:Developer>
				3888	</gjob:Developer>
				3889	</gjob:Developers>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3890
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3891	<gjob:Contact>
				3892	<gjob:Person>Nathan Clemons</gjob:Person>
				3893	<gjob:Email>nathan@windsofstorm.net</gjob:Email>
				3894	<gjob:Company>
				3895	</gjob:Company>
				3896	<gjob:Organisation>
				3897	</gjob:Organisation>
				3898	<gjob:Webpage>
				3899	</gjob:Webpage>
				3900	<gjob:Snailmail>
				3901	</gjob:Snailmail>
				3902	<gjob:Phone>
				3903	</gjob:Phone>
				3904	</gjob:Contact>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3905
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3906	<gjob:Requirements>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3907	The program should be released as free software, under the GPL.
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3908	</gjob:Requirements>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3909
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3910	<gjob:Skills>
				3911	</gjob:Skills>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3912
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3913	<gjob:Details>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3914	A GNOME based system that will allow a superuser to configure
				3915	compressed and uncompressed files and/or file systems to be backed
				3916	up with a supported media in the system. This should be able to
				3917	perform via find commands generating a list of files that are passed
				3918	to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
				3919	or via operations performed on the filesystem itself. Email
				3920	notification and GUI status display very important.
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3921	</gjob:Details>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3922
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3923	</gjob:Job>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3924
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3925	</gjob:Jobs>
				3926	</gjob:Helping></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3927
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3928	<p>While loading the XML file into an internal DOM tree is a matter of
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3929	calling only a couple of functions, browsing the tree to gather the data and
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3930	generate the internal structures is harder, and more error prone.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3931
				3932	<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]	3933	structure. For example, the ordering of the attributes is not significant,
				3934	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]	3935	depend on the order of the children of a given node, unless it really makes
				3936	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]	3937	<pre>/*
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3938	* A person record
				3939	*/
				3940	typedef struct person {
				3941	char *name;
				3942	char *email;
				3943	char *company;
				3944	char *organisation;
				3945	char *smail;
				3946	char *webPage;
				3947	char *phone;
				3948	} person, *personPtr;
				3949
				3950	/*
				3951	* And the code needed to parse it
				3952	*/
				3953	personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
				3954	personPtr ret = NULL;
				3955
				3956	DEBUG("parsePerson\n");
				3957	/*
				3958	* allocate the struct
				3959	*/
				3960	ret = (personPtr) malloc(sizeof(person));
				3961	if (ret == NULL) {
				3962	fprintf(stderr,"out of memory\n");
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3963	return(NULL);
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3964	}
				3965	memset(ret, 0, sizeof(person));
				3966
				3967	/* We don't care what the top level element name is */
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3968	cur = cur->xmlChildrenNode;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3969	while (cur != NULL) {
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3970	if ((!strcmp(cur->name, "Person")) && (cur->ns == ns))
				3971	ret->name = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				3972	if ((!strcmp(cur->name, "Email")) && (cur->ns == ns))
				3973	ret->email = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				3974	cur = cur->next;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3975	}
				3976
				3977	return(ret);
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3978	}</pre>
				3979
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3980	<p>Here are a couple of things to notice:</p>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3981	<ul>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3982	<li>Usually a recursive parsing style is the more convenient one: XML data
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3983	is by nature subject to repetitive constructs and usually exhibits highly
				3984	structured patterns.</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3985	<li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
				3986	i.e. the pointer to the global XML document and the namespace reserved to
				3987	the application. Document wide information are needed for example to
				3988	decode entities and it's a good coding practice to define a namespace for
				3989	your application set of data and test that the element and attributes
				3990	you're analyzing actually pertains to your application space. This is
				3991	done by a simple equality test (cur->ns == ns).</li>
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3992	<li>To retrieve text and attributes value, you can use the function
				3993	<em>xmlNodeListGetString</em> to gather all the text and entity reference
				3994	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]	3995	</ul>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3996
				3997	<p>Here is another piece of code used to parse another level of the
				3998	structure:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3999	<pre>#include <libxml/tree.h>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	4000	/*
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4001	* a Description for a Job
				4002	*/
				4003	typedef struct job {
				4004	char *projectID;
				4005	char *application;
				4006	char *category;
				4007	personPtr contact;
				4008	int nbDevelopers;
				4009	personPtr developers[100]; /* using dynamic alloc is left as an exercise */
				4010	} job, *jobPtr;
				4011
				4012	/*
				4013	* And the code needed to parse it
				4014	*/
				4015	jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
				4016	jobPtr ret = NULL;
				4017
				4018	DEBUG("parseJob\n");
				4019	/*
				4020	* allocate the struct
				4021	*/
				4022	ret = (jobPtr) malloc(sizeof(job));
				4023	if (ret == NULL) {
				4024	fprintf(stderr,"out of memory\n");
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4025	return(NULL);
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4026	}
				4027	memset(ret, 0, sizeof(job));
				4028
				4029	/* We don't care what the top level element name is */
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	4030	cur = cur->xmlChildrenNode;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4031	while (cur != NULL) {
				4032
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	4033	if ((!strcmp(cur->name, "Project")) && (cur->ns == ns)) {
				4034	ret->projectID = xmlGetProp(cur, "ID");
				4035	if (ret->projectID == NULL) {
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4036	fprintf(stderr, "Project has no ID\n");
				4037	}
				4038	}
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	4039	if ((!strcmp(cur->name, "Application")) && (cur->ns == ns))
				4040	ret->application = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				4041	if ((!strcmp(cur->name, "Category")) && (cur->ns == ns))
				4042	ret->category = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				4043	if ((!strcmp(cur->name, "Contact")) && (cur->ns == ns))
				4044	ret->contact = parsePerson(doc, ns, cur);
				4045	cur = cur->next;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4046	}
				4047
				4048	return(ret);
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4049	}</pre>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4050
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	4051	<p>Once you are used to it, writing this kind of code is quite simple, but
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	4052	boring. Ultimately, it could be possible to write stubbers taking either C
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	4053	data structure definitions, a set of XML examples or an XML DTD and produce
				4054	the code needed to import and export the content between C data and XML
				4055	storage. This is left as an exercise to the reader :-)</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4056
Daniel Veillard	6f0adb5	2000-07-03 11:41:26 +0000	[diff] [blame]	4057	<p>Feel free to use <a href="example/gjobread.c">the code for the full C
				4058	parsing example</a> as a template, it is also available with Makefile in the
				4059	Gnome CVS base under gnome-xml/example</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4060
Daniel Veillard	c310d56	2000-06-23 18:32:15 +0000	[diff] [blame]	4061	<h2><a name="Contributi">Contributions</a></h2>
				4062	<ul>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	4063	<li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
				4064	patches, Gary Pennington worked on the validation API, threading support
				4065	and Solaris port.</li>
				4066	<li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	4067	<li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
				4068	maintainer of the Windows port, <a
				4069	href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
				4070	binaries</a></li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4071	<li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
				4072	<a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	4073	<li><a
				4074	href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	4075	Sergeant</a> developed <a
				4076	href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4077	libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
				4078	application server</a></li>
				4079	<li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
				4080	href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillard	ca98976	2001-06-23 17:39:29 +0000	[diff] [blame]	4081	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]	4082	documentation</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4083	<li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
				4084	href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard	5168dbf	2001-07-07 00:18:23 +0000	[diff] [blame]	4085	<li>there is a module for <a
				4086	href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
				4087	in OpenNSD/AOLServer</a></li>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	4088	<li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the
				4089	first version of libxml/libxslt <a
				4090	href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li>
Daniel Veillard	1aadc44	2001-11-28 13:10:32 +0000	[diff] [blame]	4091	<li>Petr Kozelka provides <a
				4092	href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
				4093	libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	4094	<li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the
				4095	<a href="http://www.w3.org/Signature/">XML Canonicalization and XML
				4096	Digital Signature</a> <a
				4097	href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li>
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	4098	<li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a>, <a
				4099	href="http://www.zveno.com/">Zveno</a> and contributors maintain <a
				4100	href="http://tclxml.sourceforge.net/">tcl bindings for libxml2 and
				4101	libxslt</a>, as well as <a
				4102	href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for
				4103	xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a>
				4104	a GUI for xsltproc.</li>
Daniel Veillard	c310d56	2000-06-23 18:32:15 +0000	[diff] [blame]	4105	</ul>
				4106
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	4107	<p></p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	4108	</body>
				4109	</html>