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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	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	5	<title>The XML C library 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	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	11	<h1 align="center">The XML C library for Gnome</h1>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	12
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	13	<h1>Note: this is the flat content of the <a href="index.html">web
				14	site</a></h1>
				15
Daniel Veillard	c948420	2001-10-24 12:35:52 +0000	[diff] [blame]	16	<h1 style="text-align: center">libxml, a.k.a. gnome-xml</h1>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	17
				18	<p></p>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	19
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	20	<p>Libxml is the XML C library developed for the Gnome project. XML itself
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	21	is a metalanguage to design markup languages, i.e. text language where
				22	semantic and structure are added to the content using extra "markup"
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	9698445	2000-08-31 13:50:12 +0000	[diff] [blame]	64	</ul>
				65
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	66	<p>In most cases libxml tries to implement the specifications in a relatively
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	67	strictly compliant way. As of release 2.4.16, libxml2 passes all 1800+ tests
				68	from the <a
Daniel Veillard	a539356	2002-02-20 11:40:49 +0000	[diff] [blame]	69	href="http://www.oasis-open.org/committees/xml-conformance/">OASIS XML Tests
				70	Suite</a>.</p>
Daniel Veillard	5b16f58	2002-02-20 11:38:46 +0000	[diff] [blame]	71
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	72	<p>To some extent libxml2 provides support for the following additional
				73	specifications but doesn't claim to implement them completely:</p>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	74	<ul>
				75	<li>Document Object Model (DOM) <a
				76	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]	77	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]	78	libxml2</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	79	<li><a href="http://www.cis.ohio-state.edu/rfc/rfc959.txt">RFC 959</a> :
				80	libxml implements a basic FTP client code</li>
				81	<li><a href="http://www.cis.ohio-state.edu/rfc/rfc1945.txt">RFC 1945</a> :
				82	HTTP/1.0, again a basic HTTP client code</li>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	83	<li>SAX: a minimal SAX implementation compatible with early expat
				84	versions</li>
				85	<li>DocBook SGML v4: libxml2 includes a hackish parser to transition to
				86	XML</li>
				87	</ul>
				88
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	89	<p>A partial implementation of XML Schemas is being worked on but it would be
				90	far too early to make any conformance statement about it at the moment.</p>
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	91
Daniel Veillard	9698445	2000-08-31 13:50:12 +0000	[diff] [blame]	92	<p>Separate documents:</p>
				93	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	94	<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]	95	implementation of XSLT 1.0 and common extensions like EXSLT for
				96	libxml2</li>
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	97	<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]	98	: a standard DOM2 implementation for libxml2</li>
				99	<li><a href="http://www.aleksey.com/xmlsec/">the XMLSec page</a>: an
				100	implementation of <a href="http://www.w3.org/TR/xmldsig-core/">W3C XML
				101	Digital Signature</a> for libxml2</li>
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	102	<li>also check the related links section below for more related and active
				103	projects.</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	104	</ul>
				105
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	106	<p>Results of the <a
				107	href="http://xmlbench.sourceforge.net/results/benchmark/index.html">xmlbench
				108	benchmark</a> on sourceforge 19 March 2003 (smaller is better):</p>
Daniel Veillard	d8da01c	2003-03-24 15:58:23 +0000	[diff] [blame^]	109
				110	<p align="center"><img src="benchmark.gif"
				111	alt="benchmark results for Expat Xerces libxml2 Oracle and Sun toolkits"></p>
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	112
Daniel Veillard	e166254	2002-08-28 11:50:59 +0000	[diff] [blame]	113	<p>Logo designed by <a href="mailto:liyanage@access.ch">Marc Liyanage</a>.</p>
				114
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	115	<h2><a name="Introducti">Introduction</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	116
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	117	<p>This document describes libxml, the <a
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	118	href="http://www.w3.org/XML/">XML</a> C library developed for the <a
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	119	href="http://www.gnome.org/">Gnome</a> project. <a
				120	href="http://www.w3.org/XML/">XML is a standard</a> for building tag-based
				121	structured documents/data.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	122
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	123	<p>Here are some key points about libxml:</p>
				124	<ul>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	125	<li>Libxml exports Push (progressive) and Pull (blocking) type parser
				126	interfaces for both XML and HTML.</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	127	<li>Libxml can do DTD validation at parse time, using a parsed document
				128	instance, or with an arbitrary DTD.</li>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	129	<li>Libxml includes complete <a
Daniel Veillard	8c2ecaf	2001-07-10 17:53:07 +0000	[diff] [blame]	130	href="http://www.w3.org/TR/xpath">XPath</a>, <a
				131	href="http://www.w3.org/TR/xptr">XPointer</a> and <a
				132	href="http://www.w3.org/TR/xinclude">XInclude</a> implementations.</li>
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	133	<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]	134	sticking closely to ANSI C/POSIX for easy embedding. Works on
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	135	Linux/Unix/Windows, ported to a number of other platforms.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	136	<li>Basic support for HTTP and FTP client allowing applications to fetch
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	137	remote resources.</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	138	<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]	139	<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]	140	href="http://www.w3.org/DOM/">DOM</a> interfaces.</li>
				141	<li>Libxml also has a <a href="http://www.megginson.com/SAX/index.html">SAX
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	142	like interface</a>; the interface is designed to be compatible with <a
				143	href="http://www.jclark.com/xml/expat.html">Expat</a>.</li>
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	144	<li>This library is released under the <a
				145	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	146	License</a>. See the Copyright file in the distribution for the precise
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	147	wording.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	148	</ul>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	149
Daniel Veillard	e0c1d72	2001-03-21 10:28:36 +0000	[diff] [blame]	150	<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]	151	Gnome-1.X library requiring it, <strong><span
Daniel Veillard	e0c1d72	2001-03-21 10:28:36 +0000	[diff] [blame]	152	style="background-color: #FF0000">Do Not Use libxml1</span></strong>, use
				153	libxml2</p>
				154
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	155	<h2><a name="FAQ">FAQ</a></h2>
				156
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	157	<p>Table of Contents:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	158	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	159	<li><a href="FAQ.html#License">License(s)</a></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	160	<li><a href="FAQ.html#Installati">Installation</a></li>
				161	<li><a href="FAQ.html#Compilatio">Compilation</a></li>
				162	<li><a href="FAQ.html#Developer">Developer corner</a></li>
				163	</ul>
				164
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	165	<h3><a name="License">License</a>(s)</h3>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	166	<ol>
				167	<li><em>Licensing Terms for libxml</em>
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	168	<p>libxml is released under the <a
				169	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	170	License</a>; see the file Copyright in the distribution for the precise
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	171	wording</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	172	</li>
				173	<li><em>Can I embed libxml in a proprietary application ?</em>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	174	<p>Yes. The MIT License allows you to keep proprietary the changes you
				175	made to libxml, but it would be graceful to send-back bug fixes and
				176	improvements as patches for possible incorporation in the main
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	177	development tree.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	178	</li>
				179	</ol>
				180
				181	<h3><a name="Installati">Installation</a></h3>
				182	<ol>
				183	<li>Unless you are forced to because your application links with a Gnome
				184	library requiring it, <strong><span style="background-color: #FF0000">Do
				185	Not Use libxml1</span></strong>, use libxml2</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	186	<li><em>Where can I get libxml</em> ?
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	187	<p>The original distribution comes from <a
				188	href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> or <a
Daniel Veillard	6581e1b	2003-02-09 22:21:43 +0000	[diff] [blame]	189	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]	190	<p>Most Linux and BSD distributions include libxml, this is probably the
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	191	safer way for end-users to use libxml.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	192	<p>David Doolin provides precompiled Windows versions at <a
				193	href="http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/ ">http://www.ce.berkeley.edu/~doolin/code/libxmlwin32/</a></p>
				194	</li>
				195	<li><em>I see libxml and libxml2 releases, which one should I install ?</em>
				196	<ul>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	197	<li>If you are not constrained by backward compatibility issues with
				198	existing applications, install libxml2 only</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	199	<li>If you are not doing development, you can safely install both.
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	200	Usually the packages <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	201	href="http://rpmfind.net/linux/RPM/libxml.html">libxml</a> and <a
				202	href="http://rpmfind.net/linux/RPM/libxml2.html">libxml2</a> are
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	203	compatible (this is not the case for development packages).</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	204	<li>If you are a developer and your system provides separate packaging
				205	for shared libraries and the development components, it is possible
				206	to install libxml and libxml2, and also <a
				207	href="http://rpmfind.net/linux/RPM/libxml-devel.html">libxml-devel</a>
				208	and <a
				209	href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml2-devel</a>
				210	too for libxml2 >= 2.3.0</li>
				211	<li>If you are developing a new application, please develop against
				212	libxml2(-devel)</li>
				213	</ul>
				214	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	215	<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]	216	<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]	217	library for libxml.so.0, you can probably safely remove it. The libxml
				218	packages provided on <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	219	href="ftp://rpmfind.net/pub/libxml/">rpmfind.net</a> provide
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	220	libxml.so.0</p>
				221	</li>
				222	<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]	223	dependencies</em>
				224	<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]	225	rebuild it locally with</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	226	<p><code>rpm --rebuild libxml(2)-xxx.src.rpm</code>.</p>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	227	<p>If everything goes well it will generate two binary rpm packages (one
				228	providing the shared libs and xmllint, and the other one, the -devel
				229	package, providing includes, static libraries and scripts needed to build
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	230	applications with libxml(2)) that you can install locally.</p>
				231	</li>
				232	</ol>
				233
				234	<h3><a name="Compilatio">Compilation</a></h3>
				235	<ol>
				236	<li><em>What is the process to compile libxml ?</em>
				237	<p>As most UNIX libraries libxml follows the "standard":</p>
				238	<p><code>gunzip -c xxx.tar.gz \| tar xvf -</code></p>
				239	<p><code>cd libxml-xxxx</code></p>
				240	<p><code>./configure --help</code></p>
				241	<p>to see the options, then the compilation/installation proper</p>
				242	<p><code>./configure [possible options]</code></p>
				243	<p><code>make</code></p>
				244	<p><code>make install</code></p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	245	<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]	246	update your list of installed shared libs.</p>
				247	</li>
				248	<li><em>What other libraries are needed to compile/install libxml ?</em>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	249	<p>Libxml does not require any other library, the normal C ANSI API
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	250	should be sufficient (please report any violation to this rule you may
				251	find).</p>
				252	<p>However if found at configuration time libxml will detect and use the
				253	following libs:</p>
				254	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	255	<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]	256	highly portable and available widely compression library.</li>
				257	<li>iconv: a powerful character encoding conversion library. It is
				258	included by default in recent glibc libraries, so it doesn't need to
				259	be installed specifically on Linux. It now seems a <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	260	href="http://www.opennc.org/onlinepubs/7908799/xsh/iconv.html">part
				261	of the official UNIX</a> specification. Here is one <a
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	262	href="http://www.gnu.org/software/libiconv/">implementation of the
				263	library</a> which source can be found <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	264	href="ftp://ftp.ilog.fr/pub/Users/haible/gnu/">here</a>.</li>
				265	</ul>
				266	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	267	<li><em>Make check fails on some platforms</em>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	268	<p>Sometimes the regression tests' results don't completely match the
				269	value produced by the parser, and the makefile uses diff to print the
				270	delta. On some platforms the diff return breaks the compilation process;
				271	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]	272	<p>Sometimes (especially on Solaris) make checks fail due to limitations
Daniel Veillard	e46182c	2002-02-12 14:29:11 +0000	[diff] [blame]	273	in make. Try using GNU-make instead.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	274	</li>
				275	<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]	276	<p>The configure script (and other Makefiles) are generated. Use the
				277	autogen.sh script to regenerate the configure script and Makefiles,
				278	like:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	279	<p><code>./autogen.sh --prefix=/usr --disable-shared</code></p>
				280	</li>
				281	<li><em>I have troubles when running make tests with gcc-3.0</em>
				282	<p>It seems the initial release of gcc-3.0 has a problem with the
				283	optimizer which miscompiles the URI module. Please use another
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	284	compiler.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	285	</li>
				286	</ol>
				287
				288	<h3><a name="Developer">Developer</a> corner</h3>
				289	<ol>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	290	<li><em>xmlDocDump() generates output on one line.</em>
				291	<p>Libxml will not <strong>invent</strong> spaces in the content of a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	292	document since <strong>all spaces in the content of a document are
				293	significant</strong>. If you build a tree from the API and want
				294	indentation:</p>
				295	<ol>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	296	<li>the correct way is to generate those yourself too.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	297	<li>the dangerous way is to ask libxml to add those blanks to your
				298	content <strong>modifying the content of your document in the
				299	process</strong>. The result may not be what you expect. There is
				300	<strong>NO</strong> way to guarantee that such a modification won't
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	301	affect other parts of the content of your document. See <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	302	href="http://xmlsoft.org/html/libxml-parser.html#XMLKEEPBLANKSDEFAULT">xmlKeepBlanksDefault
				303	()</a> and <a
				304	href="http://xmlsoft.org/html/libxml-tree.html#XMLSAVEFORMATFILE">xmlSaveFormatFile
				305	()</a></li>
				306	</ol>
				307	</li>
				308	<li>Extra nodes in the document:
				309	<p><em>For a XML file as below:</em></p>
				310	<pre><?xml version="1.0"?>
				311	<PLAN xmlns="http://www.argus.ca/autotest/1.0/">
				312	<NODE CommFlag="0"/>
				313	<NODE CommFlag="1"/>
				314	</PLAN></pre>
				315	<p><em>after parsing it with the function
				316	pxmlDoc=xmlParseFile(...);</em></p>
				317	<p><em>I want to the get the content of the first node (node with the
				318	CommFlag="0")</em></p>
				319	<p><em>so I did it as following;</em></p>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	320	<pre>xmlNodePtr pnode;
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	321	pnode=pxmlDoc->children->children;</pre>
				322	<p><em>but it does not work. If I change it to</em></p>
				323	<pre>pnode=pxmlDoc->children->children->next;</pre>
				324	<p><em>then it works. Can someone explain it to me.</em></p>
				325	<p></p>
				326	<p>In XML all characters in the content of the document are significant
				327	<strong>including blanks and formatting line breaks</strong>.</p>
				328	<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]	329	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]	330	to forget. There is a function <a
				331	href="http://xmlsoft.org/html/libxml-parser.html">xmlKeepBlanksDefault
				332	()</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]	333	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]	334	mixed-content in the document.</p>
				335	</li>
				336	<li><em>I get compilation errors of existing code like when accessing
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	337	<strong>root</strong> or <strong>child fields</strong> of nodes.</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	338	<p>You are compiling code developed for libxml version 1 and using a
				339	libxml2 development environment. Either switch back to libxml v1 devel or
				340	even better fix the code to compile with libxml2 (or both) by <a
				341	href="upgrade.html">following the instructions</a>.</p>
				342	</li>
				343	<li><em>I get compilation errors about non existing
				344	<strong>xmlRootNode</strong> or <strong>xmlChildrenNode</strong>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	345	fields.</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	346	<p>The source code you are using has been <a
				347	href="upgrade.html">upgraded</a> to be able to compile with both libxml
				348	and libxml2, but you need to install a more recent version:
				349	libxml(-devel) >= 1.8.8 or libxml2(-devel) >= 2.1.0</p>
				350	</li>
				351	<li><em>XPath implementation looks seriously broken</em>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	352	<p>XPath implementation prior to 2.3.0 was really incomplete. Upgrade to
				353	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]	354	</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	355	<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]	356	<p>It's hard to maintain the documentation in sync with the code
				357	<grin/> ...</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	358	<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]	359	patches.</p>
				360	</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	361	<li><em>Where can I get more examples and information than privoded on the
				362	web page?</em>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	363	<p>Ideally a libxml book would be nice. I have no such plan ... But you
				364	can:</p>
				365	<ul>
				366	<li>check more deeply the <a href="html/libxml-lib.html">existing
				367	generated doc</a></li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	368	<li>look for examples of use for libxml function using the Gnome code.
				369	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]	370	use of the <strong>xmlAddChild()</strong> function:
				371	<p><a
				372	href="http://cvs.gnome.org/lxr/search?string=xmlAddChild">http://cvs.gnome.org/lxr/search?string=xmlAddChild</a></p>
				373	<p>This may be slow, a large hardware donation to the gnome project
				374	could cure this :-)</p>
				375	</li>
				376	<li><a
				377	href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gnome-xml">Browse
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	378	the libxml source</a> , I try to write code as clean and documented
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	379	as possible, so looking at it may be helpful. In particular the code
				380	of xmllint.c and of the various testXXX.c test programs should
				381	provide good examples of how to do things with the library.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	382	</ul>
				383	</li>
				384	<li>What about C++ ?
				385	<p>libxml is written in pure C in order to allow easy reuse on a number
				386	of platforms, including embedded systems. I don't intend to convert to
				387	C++.</p>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	388	<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]	389	<ul>
				390	<li>by Ari Johnson <ari@btigate.com>:
				391	<p>Website: <a
				392	href="http://lusis.org/~ari/xml++/">http://lusis.org/~ari/xml++/</a></p>
				393	<p>Download: <a
				394	href="http://lusis.org/~ari/xml++/libxml++.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a></p>
				395	</li>
				396	<li>by Peter Jones <pjones@pmade.org>
				397	<p>Website: <a
				398	href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
				399	</li>
				400	</ul>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	401	</li>
				402	<li>How to validate a document a posteriori ?
				403	<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]	404	initial parsing time or documents which have been built from scratch
				405	using the API. Use the <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	406	href="http://xmlsoft.org/html/libxml-valid.html#XMLVALIDATEDTD">xmlValidateDtd()</a>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	407	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]	408	document:</p>
				409	<pre>xmlDocPtr doc; /* your existing document */
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	410	xmlDtdPtr dtd = xmlParseDTD(NULL, filename_of_dtd); /* parse the DTD */
				411
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	412	dtd->name = xmlStrDup((xmlChar)"root_name"); / use the given root */
				413
				414	doc->intSubset = dtd;
				415	if (doc->children == NULL) xmlAddChild((xmlNodePtr)doc, (xmlNodePtr)dtd);
				416	else xmlAddPrevSibling(doc->children, (xmlNodePtr)dtd);
				417	</pre>
				418	</li>
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	419	<li>So what is this funky "xmlChar" used all the time?
				420	<p>It is a null terminated sequence of utf-8 characters. And only utf-8!
				421	You need to convert strings encoded in different ways to utf-8 before
				422	passing them to the API. This can be accomplished with the iconv library
				423	for instance.</p>
John Fleck	61f6fb6	2002-10-31 15:23:29 +0000	[diff] [blame]	424	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	425	<li>etc ...</li>
				426	</ol>
				427
				428	<p></p>
				429
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	430	<h2><a name="Documentat">Documentation</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	431
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	432	<p>There are several on-line resources related to using libxml:</p>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	433	<ol>
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	434	<li>Use the <a href="search.php">search engine</a> to lookup
				435	informations.</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	436	<li>Check the <a href="FAQ.html">FAQ.</a></li>
Daniel Veillard	c19fccc	2000-07-03 11:52:01 +0000	[diff] [blame]	437	<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]	438	documentation</a> automatically extracted from code comments (using <a
				439	href="http://cvs.gnome.org/bonsai/rview.cgi?cvsroot=/cvs/gnome&dir=gtk-doc">gtk
				440	doc</a>).</li>
Daniel Veillard	8d86964	2000-07-14 12:12:59 +0000	[diff] [blame]	441	<li>Look at the documentation about <a href="encoding.html">libxml
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	442	internationalization support</a>.</li>
Daniel Veillard	bc66f85	2002-01-14 09:49:20 +0000	[diff] [blame]	443	<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]	444	examples</a> on how to use libxml.</li>
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	445	<li>John Fleck's libxml tutorial: <a href="tutorial/index.html">html</a> or
				446	<a href="tutorial/xmltutorial.pdf">pdf</a>.</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	447	<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]	448	href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">some nice
				449	documentation</a> explaining how to use the libxml SAX interface.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	450	<li>George Lebl wrote <a
				451	href="http://www-4.ibm.com/software/developer/library/gnome3/">an article
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	452	for IBM developerWorks</a> about using libxml.</li>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	453	<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]	454	file</a>.</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	455	<li>Read the <a href="upgrade.html">1.x to 2.x upgrade path</a>
				456	description. If you are starting a new project using libxml you should
				457	really use the 2.x version.</li>
Daniel Veillard	845cce4	2002-01-09 11:51:37 +0000	[diff] [blame]	458	<li>And don't forget to look at the <a
				459	href="http://mail.gnome.org/archives/xml/">mailing-list archive</a>.</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	460	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	461
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	462	<h2><a name="Reporting">Reporting bugs and getting help</a></h2>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	463
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	464	<p>Well, bugs or missing features are always possible, and I will make a
				465	point of fixing them in a timely fashion. The best way to report a bug is to
				466	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]	467	bug tracking database</a> (make sure to use the "libxml2" module name). I
				468	look at reports there regularly and it's good to have a reminder when a bug
				469	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]	470
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	471	<p>There is also a mailing-list <a
Daniel Veillard	3197f16	2001-04-04 00:40:08 +0000	[diff] [blame]	472	href="mailto:xml@gnome.org">xml@gnome.org</a> for libxml, with an <a
				473	href="http://mail.gnome.org/archives/xml/">on-line archive</a> (<a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	474	href="http://xmlsoft.org/messages">old</a>). To subscribe to this list,
				475	please visit the <a
				476	href="http://mail.gnome.org/mailman/listinfo/xml">associated Web</a> page and
				477	follow the instructions. <strong>Do not send code, I won't debug it</strong>
				478	(but patches are really appreciated!).</p>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	479
Daniel Veillard	008186f	2001-09-13 14:24:44 +0000	[diff] [blame]	480	<p>Check the following <strong><span style="color: #FF0000">before
				481	posting</span></strong>:</p>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	482	<ul>
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	483	<li>Read the <a href="FAQ.html">FAQ</a> and <a href="search.php">use the
				484	search engine</a> to get informations related to your problem.</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	485	<li>Make sure you are <a href="ftp://xmlsoft.org/">using a recent
				486	version</a>, and that the problem still shows up in a recent version.</li>
				487	<li>Check the <a href="http://mail.gnome.org/archives/xml/">list
				488	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]	489	there is probably a fix available, similarly check the <a
Daniel Veillard	e7ead2d	2001-08-22 23:44:09 +0000	[diff] [blame]	490	href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">registered
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	491	open bugs</a>.</li>
				492	<li>Make sure you can reproduce the bug with xmllint or one of the test
				493	programs found in source in the distribution.</li>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	494	<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]	495	attachment)</li>
Daniel Veillard	234547b	2001-07-05 09:46:10 +0000	[diff] [blame]	496	</ul>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	497
Daniel Veillard	dadd087	2001-09-15 09:21:44 +0000	[diff] [blame]	498	<p>Then send the bug with associated informations to reproduce it to the <a
Daniel Veillard	33a6780	2001-03-07 09:44:02 +0000	[diff] [blame]	499	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]	500	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]	501	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]	502	answer a given question, ask on the list.</p>
				503
				504	<p>To <span style="color: #E50000">be really clear about support</span>:</p>
				505	<ul>
				506	<li>Support or help <span style="color: #E50000">request MUST be sent to
				507	the list or on bugzilla</span> in case of problems, so that the Question
				508	and Answers can be shared publicly. Failing to do so carries the implicit
				509	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]	510	others" and is not welcome. I will automatically Carbon-Copy the
				511	xml@gnome.org mailing list for any technical reply made about libxml2 or
				512	libxslt.</li>
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	513	<li>There is <span style="color: #E50000">no garantee for support</span>,
				514	if your question remains unanswered after a week, repost it, making sure
				515	you gave all the detail needed and the informations requested.</li>
				516	<li>Failing to provide informations as requested or double checking first
				517	for prior feedback also carries the implicit message "the time of the
				518	library maintainers is less valuable than my time" and might not be
				519	welcome.</li>
				520	</ul>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	521
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	522	<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]	523	probably be processed faster than those without.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	524
				525	<p>If you're looking for help, a quick look at <a
Daniel Veillard	f7ed336	2001-08-17 12:01:21 +0000	[diff] [blame]	526	href="http://mail.gnome.org/archives/xml/">the list archive</a> may actually
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	527	provide the answer. I usually send source samples when answering libxml usage
Daniel Veillard	6f0adb5	2000-07-03 11:41:26 +0000	[diff] [blame]	528	questions. The <a href="http://xmlsoft.org/html/book1.html">auto-generated
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	529	documentation</a> is not as polished as I would like (i need to learn more
				530	about DocBook), but it's a good starting point.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	531
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	532	<h2><a name="help">How to help</a></h2>
				533
				534	<p>You can help the project in various ways, the best thing to do first is to
				535	subscribe to the mailing-list as explained before, check the <a
Daniel Veillard	f7ed336	2001-08-17 12:01:21 +0000	[diff] [blame]	536	href="http://mail.gnome.org/archives/xml/">archives </a>and the <a
				537	href="http://bugzilla.gnome.org/buglist.cgi?product=libxml">Gnome bug
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	538	database</a>:</p>
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	539	<ol>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	540	<li>Provide patches when you find problems.</li>
				541	<li>Provide the diffs when you port libxml to a new platform. They may not
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	542	be integrated in all cases but help pinpointing portability problems
				543	and</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	544	<li>Provide documentation fixes (either as patches to the code comments or
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	545	as HTML diffs).</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	546	<li>Provide new documentations pieces (translations, examples, etc
				547	...).</li>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	548	<li>Check the TODO file and try to close one of the items.</li>
				549	<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]	550	provide a fix. <a href="mailto:daniel@veillard.com">Get in touch with me
				551	</a>before to avoid synchronization problems and check that the suggested
				552	fix will fit in nicely :-)</li>
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	553	</ol>
				554
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	555	<h2><a name="Downloads">Downloads</a></h2>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	556
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	557	<p>The latest versions of libxml can be found on <a
Daniel Veillard	20c8cf2	2001-06-26 22:47:36 +0000	[diff] [blame]	558	href="ftp://xmlsoft.org/">xmlsoft.org</a> (<a
				559	href="ftp://speakeasy.rpmfind.net/pub/libxml/">Seattle</a>, <a
				560	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]	561	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]	562	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]	563	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]	564	href="ftp://ftp.gnome.org/pub/GNOME/stable/redhat/i386/libxml/">RPM
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	565	packages</a> -->
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	566	, 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]	567	mirror in Austria</a>. (NOTE that you need both the <a
Daniel Veillard	c19fccc	2000-07-03 11:52:01 +0000	[diff] [blame]	568	href="http://rpmfind.net/linux/RPM/libxml2.html">libxml(2)</a> and <a
				569	href="http://rpmfind.net/linux/RPM/libxml2-devel.html">libxml(2)-devel</a>
Daniel Veillard	9518953	2001-07-26 18:30:26 +0000	[diff] [blame]	570	packages installed to compile applications using libxml.) <a
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	571	href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the maintainer of
				572	the Windows port, <a
				573	href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
				574	binaries</a>. <a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a>
				575	provides <a href="http://garypennington.net/libxml2/">Solaris binaries</a>.
				576	<a href="mailto:Steve.Ball@zveno.com">Steve Ball</a> provides <a
				577	href="http://www.zveno.com/open_source/libxml2xslt.html">Mac Os X
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	578	binaries</a>.</p>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	579
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	580	<p><a name="Snapshot">Snapshot:</a></p>
				581	<ul>
				582	<li>Code from the W3C cvs base libxml <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	583	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]	584	<li>Docs, content of the web site, the list archive included <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	585	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]	586	</ul>
				587
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	588	<p><a name="Contribs">Contributions:</a></p>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	589
				590	<p>I do accept external contributions, especially if compiling on another
Daniel Veillard	c6271d2	2001-10-27 07:50:58 +0000	[diff] [blame]	591	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]	592	languages have been provided, and can be found in the <a
				593	href="contribs.html">contrib section</a></p>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	594
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	595	<p>Libxml is also available from CVS:</p>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	596	<ul>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	597	<li><p>The <a
				598	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]	599	CVS base</a>. Check the <a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	600	href="http://developer.gnome.org/tools/cvs.html">Gnome CVS Tools</a>
				601	page; the CVS module is <b>gnome-xml</b>.</p>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	602	</li>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	603	<li>The <strong>libxslt</strong> module is also present there</li>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	604	</ul>
				605
				606	<h2><a name="News">News</a></h2>
				607
Daniel Veillard	944b5ff	1999-12-15 19:08:24 +0000	[diff] [blame]	608	<h3>CVS only : check the <a
				609	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]	610	for a really accurate description</h3>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	611
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	612	<p>Items not finished and worked on, get in touch with the list if you want
				613	to test those</p>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	614	<ul>
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	615	<li>More testing on RelaxNG</li>
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	616	<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]	617	Schemas</a></li>
				618	</ul>
				619
Daniel Veillard	d8da01c	2003-03-24 15:58:23 +0000	[diff] [blame^]	620	<p>2.5.5: Mar 24 2003</p>
				621	<ul>
				622	<li>Lot of fixes on the Relax NG implementation. More testing including
				623	DocBook and TEI examples.</li>
				624	<li>Increased the support for W3C XML Schemas datatype</li>
				625	<li>Several bug fixes in the URI handling layer</li>
				626	<li>Bug fixes: HTML parser, xmlReader, DTD validation, XPath, encoding
				627	conversion, line counting in the parser.</li>
				628	<li>Added support for $XMLLINT_INDENT environment variable, FTP delete</li>
				629	<li>Fixed the RPM spec file name</li>
				630	</ul>
				631
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	632	<h3>2.5.4: Feb 20 2003</h3>
				633	<ul>
				634	<li>Conformance testing and lot of fixes on Relax NG and XInclude
				635	implementation</li>
				636	<li>Implementation of XPointer element() scheme</li>
				637	<li>Bug fixes: XML parser, XInclude entities merge, validity checking on
				638	namespaces,
				639	<p>2 serialization bugs, node info generation problems, a DTD regexp
				640	generation problem.</p>
				641	</li>
				642	<li>Portability: windows updates and path canonicalization (Igor)</li>
				643	<li>A few typo fixes (Kjartan Maraas)</li>
				644	<li>Python bindings generator fixes (Stephane Bidoul)</li>
				645	</ul>
				646
Daniel Veillard	1d788d2	2003-02-10 16:21:58 +0000	[diff] [blame]	647	<h3>2.5.3: Feb 10 2003</h3>
				648	<ul>
				649	<li>RelaxNG and XML Schemas datatypes improvements, and added a first
				650	version of RelaxNG Python bindings</li>
				651	<li>Fixes: XLink (Sean Chittenden), XInclude (Sean Chittenden), API fix for
				652	serializing namespace nodes, encoding conversion bug, XHTML1
				653	serialization</li>
				654	<li>Portability fixes: Windows (Igor), AMD 64bits RPM spec file</li>
				655	</ul>
				656
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	657	<h3>2.5.2: Feb 5 2003</h3>
				658	<ul>
				659	<li>First implementation of RelaxNG, added --relaxng flag to xmllint</li>
				660	<li>Schemas support now compiled in by default.</li>
				661	<li>Bug fixes: DTD validation, namespace checking, XInclude and entities,
				662	delegateURI in XML Catalogs, HTML parser, XML reader (Stéphane Bidoul),
				663	XPath parser and evaluation, UTF8ToUTF8 serialization, XML reader memory
				664	consumption, HTML parser, HTML serialization in the presence of
				665	namespaces</li>
				666	<li>added an HTML API to check elements and attributes.</li>
				667	<li>Documentation improvement, PDF for the tutorial (John Fleck), doc
				668	patches (Stefan Kost)</li>
				669	<li>Portability fixes: NetBSD (Julio Merino), Windows (Igor Zlatkovic)</li>
				670	<li>Added python bindings for XPointer, contextual error reporting
				671	(Stéphane Bidoul)</li>
				672	<li>URI/file escaping problems (Stefano Zacchiroli)</li>
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	673	</ul>
				674
Daniel Veillard	e2830f1	2003-01-08 17:47:49 +0000	[diff] [blame]	675	<h3>2.5.1: Jan 8 2003</h3>
				676	<ul>
				677	<li>Fixes a memory leak and configuration/compilation problems in 2.5.0</li>
				678	<li>documentation updates (John)</li>
				679	<li>a couple of XmlTextReader fixes</li>
				680	</ul>
				681
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	682	<h3>2.5.0: Jan 6 2003</h3>
				683	<ul>
				684	<li>New <a href="xmlreader.html">XmltextReader interface</a> based on C#
				685	API (with help of Stéphane Bidoul)</li>
				686	<li>Windows: more exports, including the new API (Igor)</li>
				687	<li>XInclude fallback fix</li>
				688	<li>Python: bindings for the new API, packaging (Stéphane Bidoul),
				689	drv_libxml2.py Python xml.sax driver (Stéphane Bidoul), fixes, speedup
				690	and iterators for Python-2.2 (Hannu Krosing)</li>
				691	<li>Tutorial fixes (john Fleck and Niraj Tolia) xmllint man update
				692	(John)</li>
				693	<li>Fix an XML parser bug raised by Vyacheslav Pindyura</li>
				694	<li>Fix for VMS serialization (Nigel Hall) and config (Craig A. Berry)</li>
				695	<li>Entities handling fixes</li>
				696	<li>new API to optionally track node creation and deletion (Lukas
				697	Schroeder)</li>
				698	<li>Added documentation for the XmltextReader interface and some <a
				699	href="guidelines.html">XML guidelines</a></li>
				700	</ul>
				701
Daniel Veillard	c1eed32	2002-12-12 11:01:32 +0000	[diff] [blame]	702	<h3>2.4.30: Dec 12 2002</h3>
				703	<ul>
				704	<li>2.4.29 broke the python bindings, rereleasing</li>
				705	<li>Improvement/fixes of the XML API generator, and couple of minor code
				706	fixes.</li>
				707	</ul>
				708
Daniel Veillard	9b4bb4d	2002-12-11 19:28:47 +0000	[diff] [blame]	709	<h3>2.4.29: Dec 11 2002</h3>
				710	<ul>
				711	<li>Windows fixes (Igor): Windows CE port, pthread linking, python bindings
				712	(Stéphane Bidoul), Mingw (Magnus Henoch), and export list updates</li>
				713	<li>Fix for prev in python bindings (ERDI Gergo)</li>
				714	<li>Fix for entities handling (Marcus Clarke)</li>
				715	<li>Refactored the XML and HTML dumps to a single code path, fixed XHTML1
				716	dump</li>
				717	<li>Fix for URI parsing when handling URNs with fragment identifiers</li>
				718	<li>Fix for HTTP URL escaping problem</li>
				719	<li>added an TextXmlReader (C#) like API (work in progress)</li>
				720	<li>Rewrote the API in XML generation script, includes a C parser and saves
				721	more informations needed for C# bindings</li>
				722	</ul>
				723
Daniel Veillard	f9c4cad	2002-11-22 15:57:07 +0000	[diff] [blame]	724	<h3>2.4.28: Nov 22 2002</h3>
				725	<ul>
				726	<li>a couple of python binding fixes</li>
				727	<li>2 bug fixes in the XML push parser</li>
				728	<li>potential memory leak removed (Martin Stoilov)</li>
				729	<li>fix to the configure script for Unix (Dimitri Papadopoulos)</li>
				730	<li>added encoding support for XInclude parse="text"</li>
				731	<li>autodetection of XHTML1 and specific serialization rules added</li>
Daniel Veillard	9b4bb4d	2002-12-11 19:28:47 +0000	[diff] [blame]	732	<li>nasty threading bug fixed (William Brack)</li>
Daniel Veillard	f9c4cad	2002-11-22 15:57:07 +0000	[diff] [blame]	733	</ul>
				734
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	735	<h3>2.4.27: Nov 17 2002</h3>
				736	<ul>
				737	<li>fixes for the Python bindings</li>
				738	<li>a number of bug fixes: SGML catalogs, xmlParseBalancedChunkMemory(),
				739	HTML parser, Schemas (Charles Bozeman), document fragment support
				740	(Christian Glahn), xmlReconciliateNs (Brian Stafford), XPointer,
				741	xmlFreeNode(), xmlSAXParseMemory (Peter Jones), xmlGetNodePath (Petr
				742	Pajas), entities processing</li>
				743	<li>added grep to xmllint --shell</li>
				744	<li>VMS update patch from Craig A. Berry</li>
				745	<li>cleanup of the Windows build with support for more compilers (Igor),
				746	better thread support on Windows</li>
				747	<li>cleanup of Unix Makefiles and spec file</li>
				748	<li>Improvements to the documentation (John Fleck)</li>
				749	</ul>
				750
Daniel Veillard	4826743	2002-10-18 11:21:38 +0000	[diff] [blame]	751	<h3>2.4.26: Oct 18 2002</h3>
				752	<ul>
				753	<li>Patches for Windows CE port, improvements on Windows paths handling</li>
				754	<li>Fixes to the validation code (DTD and Schemas), xmlNodeGetPath() ,
				755	HTML serialization, Namespace compliance, and a number of small
				756	problems</li>
				757	</ul>
				758
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	759	<h3>2.4.25: Sep 26 2002</h3>
				760	<ul>
				761	<li>A number of bug fixes: XPath, validation, Python bindings, DOM and
				762	tree, xmlI/O, Html</li>
				763	<li>Serious rewrite of XInclude</li>
				764	<li>Made XML Schemas regexp part of the default build and APIs, small fix
				765	and improvement of the regexp core</li>
				766	<li>Changed the validation code to reuse XML Schemas regexp APIs</li>
				767	<li>Better handling of Windows file paths, improvement of Makefiles (Igor,
				768	Daniel Gehriger, Mark Vakoc)</li>
				769	<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]	770	APIs</li>
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	771	<li>New logos from Marc Liyanage</li>
				772	<li>Tutorial improvements: John Fleck, Christopher Harris</li>
				773	<li>Makefile: Fixes for AMD x86_64 (Mandrake), DESTDIR (Christophe
				774	Merlet)</li>
				775	<li>removal of all stderr/perror use for error reporting</li>
				776	<li>Better error reporting: XPath and DTD validation</li>
				777	<li>update of the trio portability layer (Bjorn Reese)</li>
				778	</ul>
				779
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	780	<p><strong>2.4.24: Aug 22 2002</strong></p>
				781	<ul>
				782	<li>XPath fixes (William), xf:escape-uri() (Wesley Terpstra)</li>
				783	<li>Python binding fixes: makefiles (William), generator, rpm build, x86-64
				784	(fcrozat)</li>
				785	<li>HTML <style> and boolean attributes serializer fixes</li>
				786	<li>C14N improvements by Aleksey</li>
Daniel Veillard	e166254	2002-08-28 11:50:59 +0000	[diff] [blame]	787	<li>doc cleanups: Rick Jones</li>
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	788	<li>Windows compiler makefile updates: Igor and Elizabeth Barham</li>
				789	<li>XInclude: implementation of fallback and xml:base fixup added</li>
				790	</ul>
				791
Daniel Veillard	782afda	2002-07-08 15:12:49 +0000	[diff] [blame]	792	<h3>2.4.23: July 6 2002</h3>
				793	<ul>
				794	<li>performances patches: Peter Jacobi</li>
				795	<li>c14n fixes, testsuite and performances: Aleksey Sanin</li>
				796	<li>added xmlDocFormatDump: Chema Celorio</li>
				797	<li>new tutorial: John Fleck</li>
				798	<li>new hash functions and performances: Sander Vesik, portability fix from
				799	Peter Jacobi</li>
				800	<li>a number of bug fixes: XPath (William Brack, Richard Jinks), XML and
				801	HTML parsers, ID lookup function</li>
				802	<li>removal of all remaining sprintf: Aleksey Sanin</li>
				803	</ul>
				804
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	805	<h3>2.4.22: May 27 2002</h3>
				806	<ul>
				807	<li>a number of bug fixes: configure scripts, base handling, parser, memory
				808	usage, HTML parser, XPath, documentation (Christian Cornelssen),
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	809	indentation, URI parsing</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	810	<li>Optimizations for XMLSec, fixing and making public some of the network
				811	protocol handlers (Aleksey)</li>
				812	<li>performance patch from Gary Pennington</li>
				813	<li>Charles Bozeman provided date and time support for XML Schemas
				814	datatypes</li>
				815	</ul>
				816
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	817	<h3>2.4.21: Apr 29 2002</h3>
				818
				819	<p>This release is both a bug fix release and also contains the early XML
				820	Schemas <a href="http://www.w3.org/TR/xmlschema-1/">structures</a> and <a
				821	href="http://www.w3.org/TR/xmlschema-2/">datatypes</a> code, beware, all
				822	interfaces are likely to change, there is huge holes, it is clearly a work in
				823	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]	824	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]	825	<ul>
				826	<li>a couple of bugs or limitations introduced in 2.4.20</li>
				827	<li>patches for Borland C++ and MSC by Igor</li>
				828	<li>some fixes on XPath strings and conformance patches by Richard
				829	Jinks</li>
				830	<li>patch from Aleksey for the ExcC14N specification</li>
				831	<li>OSF/1 bug fix by Bjorn</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	832	</ul>
				833
Daniel Veillard	a7084cd	2002-04-15 17:12:47 +0000	[diff] [blame]	834	<h3>2.4.20: Apr 15 2002</h3>
				835	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	836	<li>bug fixes: file descriptor leak, XPath, HTML output, DTD validation</li>
Daniel Veillard	a7084cd	2002-04-15 17:12:47 +0000	[diff] [blame]	837	<li>XPath conformance testing by Richard Jinks</li>
				838	<li>Portability fixes: Solaris, MPE/iX, Windows, OSF/1, python bindings,
				839	libxml.m4</li>
				840	</ul>
				841
Daniel Veillard	1927409	2002-03-25 16:48:03 +0000	[diff] [blame]	842	<h3>2.4.19: Mar 25 2002</h3>
				843	<ul>
				844	<li>bug fixes: half a dozen XPath bugs, Validation, ISO-Latin to UTF8
				845	encoder</li>
				846	<li>portability fixes in the HTTP code</li>
Daniel Veillard	b2fb8ed	2002-04-01 09:33:12 +0000	[diff] [blame]	847	<li>memory allocation checks using valgrind, and profiling tests</li>
Daniel Veillard	1927409	2002-03-25 16:48:03 +0000	[diff] [blame]	848	<li>revamp of the Windows build and Makefiles</li>
				849	</ul>
				850
Daniel Veillard	34ce8be	2002-03-18 19:37:11 +0000	[diff] [blame]	851	<h3>2.4.18: Mar 18 2002</h3>
				852	<ul>
				853	<li>bug fixes: tree, SAX, canonicalization, validation, portability,
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	854	XPath</li>
Daniel Veillard	34ce8be	2002-03-18 19:37:11 +0000	[diff] [blame]	855	<li>removed the --with-buffer option it was becoming unmaintainable</li>
				856	<li>serious cleanup of the Python makefiles</li>
				857	<li>speedup patch to XPath very effective for DocBook stylesheets</li>
				858	<li>Fixes for Windows build, cleanup of the documentation</li>
				859	</ul>
				860
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	861	<h3>2.4.17: Mar 8 2002</h3>
				862	<ul>
				863	<li>a lot of bug fixes, including "namespace nodes have no parents in
				864	XPath"</li>
				865	<li>fixed/improved the Python wrappers, added more examples and more
				866	regression tests, XPath extension functions can now return node-sets</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	867	<li>added the XML Canonicalization support from Aleksey Sanin</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	868	</ul>
				869
Daniel Veillard	5f4b599	2002-02-20 10:22:49 +0000	[diff] [blame]	870	<h3>2.4.16: Feb 20 2002</h3>
				871	<ul>
				872	<li>a lot of bug fixes, most of them were triggered by the XML Testsuite
				873	from OASIS and W3C. Compliance has been significantly improved.</li>
				874	<li>a couple of portability fixes too.</li>
				875	</ul>
				876
Daniel Veillard	397ff11	2002-02-11 18:27:20 +0000	[diff] [blame]	877	<h3>2.4.15: Feb 11 2002</h3>
				878	<ul>
				879	<li>Fixed the Makefiles, especially the python module ones</li>
				880	<li>A few bug fixes and cleanup</li>
				881	<li>Includes cleanup</li>
				882	</ul>
				883
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	884	<h3>2.4.14: Feb 8 2002</h3>
				885	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	886	<li>Change of License to the <a
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	887	href="http://www.opensource.org/licenses/mit-license.html">MIT
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	888	License</a> basically for integration in XFree86 codebase, and removing
				889	confusion around the previous dual-licensing</li>
Daniel Veillard	b6c1e2f	2002-02-08 14:52:52 +0000	[diff] [blame]	890	<li>added Python bindings, beta software but should already be quite
				891	complete</li>
				892	<li>a large number of fixes and cleanups, especially for all tree
				893	manipulations</li>
				894	<li>cleanup of the headers, generation of a reference API definition in
				895	XML</li>
				896	</ul>
				897
				898	<h3>2.4.13: Jan 14 2002</h3>
Daniel Veillard	744683d	2002-01-14 17:30:20 +0000	[diff] [blame]	899	<ul>
				900	<li>update of the documentation: John Fleck and Charlie Bozeman</li>
				901	<li>cleanup of timing code from Justin Fletcher</li>
				902	<li>fixes for Windows and initial thread support on Win32: Igor and Serguei
				903	Narojnyi</li>
				904	<li>Cygwin patch from Robert Collins</li>
				905	<li>added xmlSetEntityReferenceFunc() for Keith Isdale work on xsldbg</li>
				906	</ul>
				907
Daniel Veillard	ef90ba7	2001-12-07 14:24:22 +0000	[diff] [blame]	908	<h3>2.4.12: Dec 7 2001</h3>
				909	<ul>
				910	<li>a few bug fixes: thread (Gary Pennington), xmllint (Geert Kloosterman),
				911	XML parser (Robin Berjon), XPointer (Danny Jamshy), I/O cleanups
				912	(robert)</li>
				913	<li>Eric Lavigne contributed project files for MacOS</li>
				914	<li>some makefiles cleanups</li>
				915	</ul>
				916
Daniel Veillard	a487105	2001-11-26 13:19:48 +0000	[diff] [blame]	917	<h3>2.4.11: Nov 26 2001</h3>
				918	<ul>
				919	<li>fixed a couple of errors in the includes, fixed a few bugs, some code
				920	cleanups</li>
				921	<li>xmllint man pages improvement by Heiko Rupp</li>
				922	<li>updated VMS build instructions from John A Fotheringham</li>
				923	<li>Windows Makefiles updates from Igor</li>
				924	</ul>
				925
Daniel Veillard	43d3f61	2001-11-10 11:57:23 +0000	[diff] [blame]	926	<h3>2.4.10: Nov 10 2001</h3>
				927	<ul>
				928	<li>URI escaping fix (Joel Young)</li>
				929	<li>added xmlGetNodePath() (for paths or XPointers generation)</li>
				930	<li>Fixes namespace handling problems when using DTD and validation</li>
				931	<li>improvements on xmllint: Morus Walter patches for --format and
				932	--encode, Stefan Kost and Heiko Rupp improvements on the --shell</li>
				933	<li>fixes for xmlcatalog linking pointed by Weiqi Gao</li>
				934	<li>fixes to the HTML parser</li>
				935	</ul>
				936
				937	<h3>2.4.9: Nov 6 2001</h3>
				938	<ul>
				939	<li>fixes more catalog bugs</li>
				940	<li>avoid a compilation problem, improve xmlGetLineNo()</li>
				941	</ul>
				942
Daniel Veillard	ed421aa	2001-11-04 21:22:45 +0000	[diff] [blame]	943	<h3>2.4.8: Nov 4 2001</h3>
				944	<ul>
				945	<li>fixed SGML catalogs broken in previous release, updated xmlcatalog
				946	tool</li>
				947	<li>fixed a compile errors and some includes troubles.</li>
				948	</ul>
				949
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	950	<h3>2.4.7: Oct 30 2001</h3>
				951	<ul>
				952	<li>exported some debugging interfaces</li>
				953	<li>serious rewrite of the catalog code</li>
				954	<li>integrated Gary Pennington thread safety patch, added configure option
				955	and regression tests</li>
				956	<li>removed an HTML parser bug</li>
				957	<li>fixed a couple of potentially serious validation bugs</li>
				958	<li>integrated the SGML DocBook support in xmllint</li>
				959	<li>changed the nanoftp anonymous login passwd</li>
				960	<li>some I/O cleanup and a couple of interfaces for Perl wrapper</li>
				961	<li>general bug fixes</li>
				962	<li>updated xmllint man page by John Fleck</li>
				963	<li>some VMS and Windows updates</li>
				964	</ul>
				965
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	966	<h3>2.4.6: Oct 10 2001</h3>
				967	<ul>
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	968	<li>added an updated man pages by John Fleck</li>
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	969	<li>portability and configure fixes</li>
				970	<li>an infinite loop on the HTML parser was removed (William)</li>
				971	<li>Windows makefile patches from Igor</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	972	<li>fixed half a dozen bugs reported for libxml or libxslt</li>
Daniel Veillard	60087f3	2001-10-10 09:45:09 +0000	[diff] [blame]	973	<li>updated xmlcatalog to be able to modify SGML super catalogs</li>
				974	</ul>
				975
Daniel Veillard	dadd087	2001-09-15 09:21:44 +0000	[diff] [blame]	976	<h3>2.4.5: Sep 14 2001</h3>
				977	<ul>
				978	<li>Remove a few annoying bugs in 2.4.4</li>
				979	<li>forces the HTML serializer to output decimal charrefs since some
				980	version of Netscape can't handle hexadecimal ones</li>
				981	</ul>
				982
				983	<h3>1.8.16: Sep 14 2001</h3>
				984	<ul>
				985	<li>maintenance release of the old libxml1 branch, couple of bug and
				986	portability fixes</li>
				987	</ul>
				988
Daniel Veillard	04382ae	2001-09-12 18:51:30 +0000	[diff] [blame]	989	<h3>2.4.4: Sep 12 2001</h3>
				990	<ul>
				991	<li>added --convert to xmlcatalog, bug fixes and cleanups of XML
				992	Catalog</li>
				993	<li>a few bug fixes and some portability changes</li>
				994	<li>some documentation cleanups</li>
				995	</ul>
				996
Daniel Veillard	3993690	2001-08-24 00:49:01 +0000	[diff] [blame]	997	<h3>2.4.3: Aug 23 2001</h3>
				998	<ul>
				999	<li>XML Catalog support see the doc</li>
				1000	<li>New NaN/Infinity floating point code</li>
				1001	<li>A few bug fixes</li>
				1002	</ul>
				1003
				1004	<h3>2.4.2: Aug 15 2001</h3>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1005	<ul>
				1006	<li>adds xmlLineNumbersDefault() to control line number generation</li>
				1007	<li>lot of bug fixes</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1008	<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]	1009	<li>inheritance of namespaces from DTD defaulted attributes</li>
				1010	<li>fixes a serious potential security bug</li>
				1011	<li>added a --format option to xmllint</li>
				1012	</ul>
				1013
				1014	<h3>2.4.1: July 24 2001</h3>
				1015	<ul>
				1016	<li>possibility to keep line numbers in the tree</li>
				1017	<li>some computation NaN fixes</li>
				1018	<li>extension of the XPath API</li>
				1019	<li>cleanup for alpha and ia64 targets</li>
				1020	<li>patch to allow saving through HTTP PUT or POST</li>
Daniel Veillard	09ab7e1	2001-07-10 15:49:44 +0000	[diff] [blame]	1021	</ul>
				1022
				1023	<h3>2.4.0: July 10 2001</h3>
				1024	<ul>
				1025	<li>Fixed a few bugs in XPath, validation, and tree handling.</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1026	<li>Fixed XML Base implementation, added a couple of examples to the
Daniel Veillard	09ab7e1	2001-07-10 15:49:44 +0000	[diff] [blame]	1027	regression tests</li>
				1028	<li>A bit of cleanup</li>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1029	</ul>
				1030
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1031	<h3>2.3.14: July 5 2001</h3>
				1032	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1033	<li>fixed some entities problems and reduce memory requirement when
				1034	substituting them</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1035	<li>lots of improvements in the XPath queries interpreter can be
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1036	substantially faster</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1037	<li>Makefiles and configure cleanups</li>
				1038	<li>Fixes to XPath variable eval, and compare on empty node set</li>
				1039	<li>HTML tag closing bug fixed</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1040	<li>Fixed an URI reference computation problem when validating</li>
Daniel Veillard	5b43fde	2001-07-05 23:31:40 +0000	[diff] [blame]	1041	</ul>
				1042
Daniel Veillard	2adbb51	2001-06-28 16:20:36 +0000	[diff] [blame]	1043	<h3>2.3.13: June 28 2001</h3>
				1044	<ul>
				1045	<li>2.3.12 configure.in was broken as well as the push mode XML parser</li>
				1046	<li>a few more fixes for compilation on Windows MSC by Yon Derek</li>
				1047	</ul>
				1048
				1049	<h3>1.8.14: June 28 2001</h3>
				1050	<ul>
				1051	<li>Zbigniew Chyla gave a patch to use the old XML parser in push mode</li>
				1052	<li>Small Makefile fix</li>
				1053	</ul>
				1054
Daniel Veillard	1164810	2001-06-26 16:08:24 +0000	[diff] [blame]	1055	<h3>2.3.12: June 26 2001</h3>
				1056	<ul>
				1057	<li>lots of cleanup</li>
				1058	<li>a couple of validation fix</li>
				1059	<li>fixed line number counting</li>
				1060	<li>fixed serious problems in the XInclude processing</li>
				1061	<li>added support for UTF8 BOM at beginning of entities</li>
				1062	<li>fixed a strange gcc optimizer bugs in xpath handling of float, gcc-3.0
				1063	miscompile uri.c (William), Thomas Leitner provided a fix for the
				1064	optimizer on Tru64</li>
				1065	<li>incorporated Yon Derek and Igor Zlatkovic fixes and improvements for
				1066	compilation on Windows MSC</li>
				1067	<li>update of libxml-doc.el (Felix Natter)</li>
				1068	<li>fixed 2 bugs in URI normalization code</li>
				1069	</ul>
				1070
Daniel Veillard	e3c81b5	2001-06-17 14:50:34 +0000	[diff] [blame]	1071	<h3>2.3.11: June 17 2001</h3>
				1072	<ul>
				1073	<li>updates to trio, Makefiles and configure should fix some portability
				1074	problems (alpha)</li>
				1075	<li>fixed some HTML serialization problems (pre, script, and block/inline
				1076	handling), added encoding aware APIs, cleanup of this code</li>
				1077	<li>added xmlHasNsProp()</li>
				1078	<li>implemented a specific PI for encoding support in the DocBook SGML
				1079	parser</li>
				1080	<li>some XPath fixes (-Infinity, / as a function parameter and namespaces
				1081	node selection)</li>
				1082	<li>fixed a performance problem and an error in the validation code</li>
				1083	<li>fixed XInclude routine to implement the recursive behaviour</li>
				1084	<li>fixed xmlFreeNode problem when libxml is included statically twice</li>
				1085	<li>added --version to xmllint for bug reports</li>
				1086	</ul>
				1087
Daniel Veillard	2e4f188	2001-06-01 10:11:57 +0000	[diff] [blame]	1088	<h3>2.3.10: June 1 2001</h3>
				1089	<ul>
				1090	<li>fixed the SGML catalog support</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1091	<li>a number of reported bugs got fixed, in XPath, iconv detection,
				1092	XInclude processing</li>
Daniel Veillard	2e4f188	2001-06-01 10:11:57 +0000	[diff] [blame]	1093	<li>XPath string function should now handle unicode correctly</li>
				1094	</ul>
				1095
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1096	<h3>2.3.9: May 19 2001</h3>
				1097
				1098	<p>Lots of bugfixes, and added a basic SGML catalog support:</p>
				1099	<ul>
				1100	<li>HTML push bugfix #54891 and another patch from Jonas Borgström</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1101	<li>some serious speed optimization again</li>
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1102	<li>some documentation cleanups</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1103	<li>trying to get better linking on Solaris (-R)</li>
Daniel Veillard	4623acd	2001-05-19 15:13:15 +0000	[diff] [blame]	1104	<li>XPath API cleanup from Thomas Broyer</li>
				1105	<li>Validation bug fixed #54631, added a patch from Gary Pennington, fixed
				1106	xmlValidGetValidElements()</li>
				1107	<li>Added an INSTALL file</li>
				1108	<li>Attribute removal added to API: #54433</li>
				1109	<li>added a basic support for SGML catalogs</li>
				1110	<li>fixed xmlKeepBlanksDefault(0) API</li>
				1111	<li>bugfix in xmlNodeGetLang()</li>
				1112	<li>fixed a small configure portability problem</li>
				1113	<li>fixed an inversion of SYSTEM and PUBLIC identifier in HTML document</li>
				1114	</ul>
				1115
Daniel Veillard	a265af7	2001-05-14 11:13:58 +0000	[diff] [blame]	1116	<h3>1.8.13: May 14 2001</h3>
				1117	<ul>
				1118	<li>bugfixes release of the old libxml1 branch used by Gnome</li>
				1119	</ul>
				1120
Daniel Veillard	3bbbe6f	2001-05-03 11:15:37 +0000	[diff] [blame]	1121	<h3>2.3.8: May 3 2001</h3>
				1122	<ul>
				1123	<li>Integrated an SGML DocBook parser for the Gnome project</li>
				1124	<li>Fixed a few things in the HTML parser</li>
				1125	<li>Fixed some XPath bugs raised by XSLT use, tried to fix the floating
				1126	point portability issue</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1127	<li>Speed improvement (8M/s for SAX, 3M/s for DOM, 1.5M/s for
				1128	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]	1129	<li>incorporated more Windows cleanup</li>
				1130	<li>added xmlSaveFormatFile()</li>
				1131	<li>fixed problems in copying nodes with entities references (gdome)</li>
				1132	<li>removed some troubles surrounding the new validation module</li>
				1133	</ul>
				1134
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1135	<h3>2.3.7: April 22 2001</h3>
				1136	<ul>
				1137	<li>lots of small bug fixes, corrected XPointer</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1138	<li>Non deterministic content model validation support</li>
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1139	<li>added xmlDocCopyNode for gdome2</li>
				1140	<li>revamped the way the HTML parser handles end of tags</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1141	<li>XPath: corrections of namespaces support and number formatting</li>
Daniel Veillard	a41123c	2001-04-22 19:31:20 +0000	[diff] [blame]	1142	<li>Windows: Igor Zlatkovic patches for MSC compilation</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1143	<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]	1144	<li>Improved validation speed sensible for DocBook</li>
				1145	<li>fixed a big bug with ID declared in external parsed entities</li>
				1146	<li>portability fixes, update of Trio from Bjorn Reese</li>
				1147	</ul>
				1148
Daniel Veillard	afc7311	2001-04-11 11:51:41 +0000	[diff] [blame]	1149	<h3>2.3.6: April 8 2001</h3>
				1150	<ul>
				1151	<li>Code cleanup using extreme gcc compiler warning options, found and
				1152	cleared half a dozen potential problem</li>
				1153	<li>the Eazel team found an XML parser bug</li>
				1154	<li>cleaned up the user of some of the string formatting function. used the
				1155	trio library code to provide the one needed when the platform is missing
				1156	them</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1157	<li>xpath: removed a memory leak and fixed the predicate evaluation
				1158	problem, extended the testsuite and cleaned up the result. XPointer seems
				1159	broken ...</li>
Daniel Veillard	afc7311	2001-04-11 11:51:41 +0000	[diff] [blame]	1160	</ul>
				1161
Daniel Veillard	56a4cb8	2001-03-24 17:00:36 +0000	[diff] [blame]	1162	<h3>2.3.5: Mar 23 2001</h3>
				1163	<ul>
				1164	<li>Biggest change is separate parsing and evaluation of XPath expressions,
				1165	there is some new APIs for this too</li>
				1166	<li>included a number of bug fixes(XML push parser, 51876, notations,
				1167	52299)</li>
				1168	<li>Fixed some portability issues</li>
				1169	</ul>
				1170
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1171	<h3>2.3.4: Mar 10 2001</h3>
				1172	<ul>
				1173	<li>Fixed bugs #51860 and #51861</li>
				1174	<li>Added a global variable xmlDefaultBufferSize to allow default buffer
				1175	size to be application tunable.</li>
				1176	<li>Some cleanup in the validation code, still a bug left and this part
				1177	should probably be rewritten to support ambiguous content model :-\</li>
				1178	<li>Fix a couple of serious bugs introduced or raised by changes in 2.3.3
				1179	parser</li>
				1180	<li>Fixed another bug in xmlNodeGetContent()</li>
				1181	<li>Bjorn fixed XPath node collection and Number formatting</li>
				1182	<li>Fixed a loop reported in the HTML parsing</li>
				1183	<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]	1184	are formatting spaces, this is for XML conformance</li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1185	</ul>
				1186
Daniel Veillard	b402c07	2001-03-01 17:28:58 +0000	[diff] [blame]	1187	<h3>2.3.3: Mar 1 2001</h3>
				1188	<ul>
				1189	<li>small change in XPath for XSLT</li>
				1190	<li>documentation cleanups</li>
				1191	<li>fix in validation by Gary Pennington</li>
				1192	<li>serious parsing performances improvements</li>
				1193	</ul>
				1194
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1195	<h3>2.3.2: Feb 24 2001</h3>
Daniel Veillard	7168110	2001-02-24 17:48:53 +0000	[diff] [blame]	1196	<ul>
				1197	<li>chasing XPath bugs, found a bunch, completed some TODO</li>
				1198	<li>fixed a Dtd parsing bug</li>
				1199	<li>fixed a bug in xmlNodeGetContent</li>
				1200	<li>ID/IDREF support partly rewritten by Gary Pennington</li>
				1201	</ul>
				1202
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1203	<h3>2.3.1: Feb 15 2001</h3>
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1204	<ul>
				1205	<li>some XPath and HTML bug fixes for XSLT</li>
				1206	<li>small extension of the hash table interfaces for DOM gdome2
				1207	implementation</li>
				1208	<li>A few bug fixes</li>
				1209	</ul>
				1210
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1211	<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]	1212	<ul>
				1213	<li>Lots of XPath bug fixes</li>
				1214	<li>Add a mode with Dtd lookup but without validation error reporting for
				1215	XSLT</li>
				1216	<li>Add support for text node without escaping (XSLT)</li>
				1217	<li>bug fixes for xmlCheckFilename</li>
				1218	<li>validation code bug fixes from Gary Pennington</li>
				1219	<li>Patch from Paul D. Smith correcting URI path normalization</li>
				1220	<li>Patch to allow simultaneous install of libxml-devel and
				1221	libxml2-devel</li>
				1222	<li>the example Makefile is now fixed</li>
				1223	<li>added HTML to the RPM packages</li>
				1224	<li>tree copying bugfixes</li>
				1225	<li>updates to Windows makefiles</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1226	<li>optimization patch from Bjorn Reese</li>
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1227	</ul>
				1228
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1229	<h3>2.2.11: Jan 4 2001</h3>
Daniel Veillard	503b893	2001-01-05 06:36:31 +0000	[diff] [blame]	1230	<ul>
				1231	<li>bunch of bug fixes (memory I/O, xpath, ftp/http, ...)</li>
				1232	<li>added htmlHandleOmittedElem()</li>
				1233	<li>Applied Bjorn Reese's IPV6 first patch</li>
				1234	<li>Applied Paul D. Smith patches for validation of XInclude results</li>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1235	<li>added XPointer xmlns() new scheme support</li>
Daniel Veillard	503b893	2001-01-05 06:36:31 +0000	[diff] [blame]	1236	</ul>
				1237
Daniel Veillard	2ddd23d	2000-11-25 10:42:19 +0000	[diff] [blame]	1238	<h3>2.2.10: Nov 25 2000</h3>
Daniel Veillard	9d343c4	2000-11-25 10:12:43 +0000	[diff] [blame]	1239	<ul>
				1240	<li>Fix the Windows problems of 2.2.8</li>
				1241	<li>integrate OpenVMS patches</li>
				1242	<li>better handling of some nasty HTML input</li>
				1243	<li>Improved the XPointer implementation</li>
				1244	<li>integrate a number of provided patches</li>
				1245	</ul>
				1246
Daniel Veillard	2ddd23d	2000-11-25 10:42:19 +0000	[diff] [blame]	1247	<h3>2.2.9: Nov 25 2000</h3>
				1248	<ul>
				1249	<li>erroneous release :-(</li>
				1250	</ul>
				1251
Daniel Veillard	28929b2	2000-11-13 18:22:49 +0000	[diff] [blame]	1252	<h3>2.2.8: Nov 13 2000</h3>
				1253	<ul>
				1254	<li>First version of <a href="http://www.w3.org/TR/xinclude">XInclude</a>
				1255	support</li>
				1256	<li>Patch in conditional section handling</li>
				1257	<li>updated MS compiler project</li>
				1258	<li>fixed some XPath problems</li>
				1259	<li>added an URI escaping function</li>
				1260	<li>some other bug fixes</li>
				1261	</ul>
				1262
				1263	<h3>2.2.7: Oct 31 2000</h3>
				1264	<ul>
				1265	<li>added message redirection</li>
				1266	<li>XPath improvements (thanks TOM !)</li>
				1267	<li>xmlIOParseDTD() added</li>
				1268	<li>various small fixes in the HTML, URI, HTTP and XPointer support</li>
				1269	<li>some cleanup of the Makefile, autoconf and the distribution content</li>
				1270	</ul>
				1271
Daniel Veillard	29a11cc	2000-10-25 13:32:39 +0000	[diff] [blame]	1272	<h3>2.2.6: Oct 25 2000:</h3>
				1273	<ul>
				1274	<li>Added an hash table module, migrated a number of internal structure to
				1275	those</li>
				1276	<li>Fixed a posteriori validation problems</li>
				1277	<li>HTTP module cleanups</li>
				1278	<li>HTML parser improvements (tag errors, script/style handling, attribute
				1279	normalization)</li>
				1280	<li>coalescing of adjacent text nodes</li>
				1281	<li>couple of XPath bug fixes, exported the internal API</li>
				1282	</ul>
				1283
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1284	<h3>2.2.5: Oct 15 2000:</h3>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	1285	<ul>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1286	<li>XPointer implementation and testsuite</li>
				1287	<li>Lot of XPath fixes, added variable and functions registration, more
				1288	tests</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1289	<li>Portability fixes, lots of enhancements toward an easy Windows build
				1290	and release</li>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1291	<li>Late validation fixes</li>
				1292	<li>Integrated a lot of contributed patches</li>
				1293	<li>added memory management docs</li>
Daniel Veillard	ab8500d	2000-10-15 21:06:19 +0000	[diff] [blame]	1294	<li>a performance problem when using large buffer seems fixed</li>
Daniel Veillard	189446d	2000-10-13 10:23:06 +0000	[diff] [blame]	1295	</ul>
				1296
				1297	<h3>2.2.4: Oct 1 2000:</h3>
				1298	<ul>
				1299	<li>main XPath problem fixed</li>
				1300	<li>Integrated portability patches for Windows</li>
				1301	<li>Serious bug fixes on the URI and HTML code</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1302	</ul>
				1303
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1304	<h3>2.2.3: Sep 17 2000</h3>
				1305	<ul>
				1306	<li>bug fixes</li>
				1307	<li>cleanup of entity handling code</li>
				1308	<li>overall review of all loops in the parsers, all sprintf usage has been
				1309	checked too</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1310	<li>Far better handling of larges Dtd. Validating against DocBook XML Dtd
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1311	works smoothly now.</li>
				1312	</ul>
				1313
				1314	<h3>1.8.10: Sep 6 2000</h3>
				1315	<ul>
				1316	<li>bug fix release for some Gnome projects</li>
				1317	</ul>
				1318
				1319	<h3>2.2.2: August 12 2000</h3>
Daniel Veillard	786d7c8	2000-08-12 23:38:57 +0000	[diff] [blame]	1320	<ul>
				1321	<li>mostly bug fixes</li>
Daniel Veillard	ec78c0f	2000-08-25 10:25:23 +0000	[diff] [blame]	1322	<li>started adding routines to access xml parser context options</li>
Daniel Veillard	786d7c8	2000-08-12 23:38:57 +0000	[diff] [blame]	1323	</ul>
				1324
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1325	<h3>2.2.1: July 21 2000</h3>
Daniel Veillard	a2679fa	2000-07-22 02:38:15 +0000	[diff] [blame]	1326	<ul>
				1327	<li>a purely bug fixes release</li>
				1328	<li>fixed an encoding support problem when parsing from a memory block</li>
				1329	<li>fixed a DOCTYPE parsing problem</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1330	<li>removed a bug in the function allowing to override the memory
				1331	allocation routines</li>
Daniel Veillard	a2679fa	2000-07-22 02:38:15 +0000	[diff] [blame]	1332	</ul>
				1333
Daniel Veillard	d5f97f8	2000-09-17 16:38:14 +0000	[diff] [blame]	1334	<h3>2.2.0: July 14 2000</h3>
Daniel Veillard	94e9060	2000-07-17 14:38:19 +0000	[diff] [blame]	1335	<ul>
				1336	<li>applied a lot of portability fixes</li>
				1337	<li>better encoding support/cleanup and saving (content is now always
				1338	encoded in UTF-8)</li>
				1339	<li>the HTML parser now correctly handles encodings</li>
				1340	<li>added xmlHasProp()</li>
				1341	<li>fixed a serious problem with &#38;</li>
				1342	<li>propagated the fix to FTP client</li>
				1343	<li>cleanup, bugfixes, etc ...</li>
				1344	<li>Added a page about <a href="encoding.html">libxml Internationalization
				1345	support</a></li>
				1346	</ul>
				1347
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1348	<h3>1.8.9: July 9 2000</h3>
				1349	<ul>
				1350	<li>fixed the spec the RPMs should be better</li>
				1351	<li>fixed a serious bug in the FTP implementation, released 1.8.9 to solve
				1352	rpmfind users problem</li>
				1353	</ul>
				1354
Daniel Veillard	6388e17	2000-07-03 16:07:19 +0000	[diff] [blame]	1355	<h3>2.1.1: July 1 2000</h3>
				1356	<ul>
				1357	<li>fixes a couple of bugs in the 2.1.0 packaging</li>
				1358	<li>improvements on the HTML parser</li>
				1359	</ul>
				1360
Daniel Veillard	3f6f7f6	2000-06-30 17:58:25 +0000	[diff] [blame]	1361	<h3>2.1.0 and 1.8.8: June 29 2000</h3>
				1362	<ul>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1363	<li>1.8.8 is mostly a commodity package for upgrading to libxml2 according
				1364	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]	1365	about &#38; charref parsing</li>
				1366	<li>2.1.0 also ease the upgrade from libxml v1 to the recent version. it
				1367	also contains numerous fixes and enhancements:
				1368	<ul>
				1369	<li>added xmlStopParser() to stop parsing</li>
				1370	<li>improved a lot parsing speed when there is large CDATA blocs</li>
				1371	<li>includes XPath patches provided by Picdar Technology</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1372	<li>tried to fix as much as possible DTD validation and namespace
Daniel Veillard	3f6f7f6	2000-06-30 17:58:25 +0000	[diff] [blame]	1373	related problems</li>
				1374	<li>output to a given encoding has been added/tested</li>
				1375	<li>lot of various fixes</li>
				1376	</ul>
				1377	</li>
				1378	</ul>
				1379
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1380	<h3>2.0.0: Apr 12 2000</h3>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1381	<ul>
				1382	<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]	1383	idea to check the 1.x to 2.x upgrade instructions. NOTE: while initially
				1384	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]	1385	workload.</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1386	<li>The include are now located under $prefix/include/libxml (instead of
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1387	$prefix/include/gnome-xml), they also are referenced by
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1388	<pre>#include <libxml/xxx.h></pre>
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1389	<p>instead of</p>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1390	<pre>#include "xxx.h"</pre>
				1391	</li>
Daniel Veillard	8f62198	2000-03-20 13:07:15 +0000	[diff] [blame]	1392	<li>a new URI module for parsing URIs and following strictly RFC 2396</li>
				1393	<li>the memory allocation routines used by libxml can now be overloaded
				1394	dynamically by using xmlMemSetup()</li>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	1395	<li>The previously CVS only tool tester has been renamed
				1396	<strong>xmllint</strong> and is now installed as part of the libxml2
				1397	package</li>
Daniel Veillard	e0aed30	2000-04-16 08:52:20 +0000	[diff] [blame]	1398	<li>The I/O interface has been revamped. There is now ways to plug in
				1399	specific I/O modules, either at the URI scheme detection level using
				1400	xmlRegisterInputCallbacks() or by passing I/O functions when creating a
				1401	parser context using xmlCreateIOParserCtxt()</li>
				1402	<li>there is a C preprocessor macro LIBXML_VERSION providing the version
				1403	number of the libxml module in use</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1404	<li>a number of optional features of libxml can now be excluded at
				1405	configure time (FTP/HTTP/HTML/XPath/Debug)</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1406	</ul>
				1407
				1408	<h3>2.0.0beta: Mar 14 2000</h3>
				1409	<ul>
				1410	<li>This is a first Beta release of libxml version 2</li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	1411	<li>It's available only from<a href="ftp://xmlsoft.org/">xmlsoft.org
				1412	FTP</a>, it's packaged as libxml2-2.0.0beta and available as tar and
				1413	RPMs</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1414	<li>This version is now the head in the Gnome CVS base, the old one is
				1415	available under the tag LIB_XML_1_X</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1416	<li>This includes a very large set of changes. From a programmatic point
				1417	of view applications should not have to be modified too much, check the
				1418	<a href="upgrade.html">upgrade page</a></li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1419	<li>Some interfaces may changes (especially a bit about encoding).</li>
				1420	<li>the updates includes:
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1421	<ul>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1422	<li>fix I18N support. ISO-Latin-x/UTF-8/UTF-16 (nearly) seems correctly
				1423	handled now</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1424	<li>Better handling of entities, especially well-formedness checking
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1425	and proper PEref extensions in external subsets</li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1426	<li>DTD conditional sections</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1427	<li>Validation now correctly handle entities content</li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1428	<li><a href="http://rpmfind.net/tools/gdome/messages/0039.html">change
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1429	structures to accommodate DOM</a></li>
Daniel Veillard	6c8b117	2000-03-01 00:40:41 +0000	[diff] [blame]	1430	</ul>
				1431	</li>
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1432	<li>Serious progress were made toward compliance, <a
				1433	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]	1434	OASIS testsuite (except the Japanese tests since I don't support that
Daniel Veillard	edfb29b	2000-03-14 19:59:05 +0000	[diff] [blame]	1435	encoding yet). This URL is rebuilt every couple of hours using the CVS
				1436	head version.</li>
Daniel Veillard	e41f2b7	2000-01-30 20:00:07 +0000	[diff] [blame]	1437	</ul>
				1438
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1439	<h3>1.8.7: Mar 6 2000</h3>
				1440	<ul>
				1441	<li>This is a bug fix release:</li>
				1442	<li>It is possible to disable the ignorable blanks heuristic used by
				1443	libxml-1.x, a new function xmlKeepBlanksDefault(0) will allow this. Note
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1444	that for adherence to XML spec, this behaviour will be disabled by
				1445	default in 2.x . The same function will allow to keep compatibility for
				1446	old code.</li>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1447	<li>Blanks in <a> </a> constructs are not ignored anymore,
				1448	avoiding heuristic is really the Right Way :-\</li>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1449	<li>The unchecked use of snprintf which was breaking libxml-1.8.6
				1450	compilation on some platforms has been fixed</li>
				1451	<li>nanoftp.c nanohttp.c: Fixed '#' and '?' stripping when processing
				1452	URIs</li>
				1453	</ul>
				1454
Daniel Veillard	e41f2b7	2000-01-30 20:00:07 +0000	[diff] [blame]	1455	<h3>1.8.6: Jan 31 2000</h3>
				1456	<ul>
				1457	<li>added a nanoFTP transport module, debugged until the new version of <a
				1458	href="http://rpmfind.net/linux/rpm2html/rpmfind.html">rpmfind</a> can use
				1459	it without troubles</li>
Daniel Veillard	da07c34	2000-01-25 18:31:22 +0000	[diff] [blame]	1460	</ul>
				1461
				1462	<h3>1.8.5: Jan 21 2000</h3>
				1463	<ul>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	1464	<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]	1465	href="http://www.w3.org/TR/REC-xml#NT-content">[43] content</a> of the
				1466	XML spec)</li>
Daniel Veillard	461a66c	2000-01-18 18:01:01 +0000	[diff] [blame]	1467	<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]	1468	<li>Jody Goldberg <jgoldberg@home.com> provided another patch trying
				1469	to solve the zlib checks problems</li>
Daniel Veillard	461a66c	2000-01-18 18:01:01 +0000	[diff] [blame]	1470	<li>The current state in gnome CVS base is expected to ship as 1.8.5 with
				1471	gnumeric soon</li>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	1472	</ul>
				1473
				1474	<h3>1.8.4: Jan 13 2000</h3>
				1475	<ul>
				1476	<li>bug fixes, reintroduced xmlNewGlobalNs(), fixed xmlNewNs()</li>
				1477	<li>all exit() call should have been removed from libxml</li>
				1478	<li>fixed a problem with INCLUDE_WINSOCK on WIN32 platform</li>
				1479	<li>added newDocFragment()</li>
Daniel Veillard	f84f71f	2000-01-05 19:54:23 +0000	[diff] [blame]	1480	</ul>
				1481
				1482	<h3>1.8.3: Jan 5 2000</h3>
				1483	<ul>
				1484	<li>a Push interface for the XML and HTML parsers</li>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1485	<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]	1486	<li>lots of bug fixes and improvement added over XMas holidays</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1487	<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]	1488	<li>added xmlRemoveProp(), xmlRemoveID() and xmlRemoveRef()</li>
				1489	<li>Fixed bugs in xmlNewNs()</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1490	<li>External entity loading code has been revamped, now it uses
Daniel Veillard	f84f71f	2000-01-05 19:54:23 +0000	[diff] [blame]	1491	xmlLoadExternalEntity(), some fix on entities processing were added</li>
Daniel Veillard	437b87b	2000-01-03 17:30:46 +0000	[diff] [blame]	1492	<li>cleaned up WIN32 includes of socket stuff</li>
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	1493	</ul>
				1494
				1495	<h3>1.8.2: Dec 21 1999</h3>
				1496	<ul>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1497	<li>I got another problem with includes and C++, I hope this issue is fixed
				1498	for good this time</li>
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	1499	<li>Added a few tree modification functions: xmlReplaceNode,
				1500	xmlAddPrevSibling, xmlAddNextSibling, xmlNodeSetName and
				1501	xmlDocSetRootElement</li>
				1502	<li>Tried to improve the HTML output with help from <a
				1503	href="mailto:clahey@umich.edu">Chris Lahey</a></li>
Daniel Veillard	e4e5131	1999-12-18 15:32:46 +0000	[diff] [blame]	1504	</ul>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1505
Daniel Veillard	e4e5131	1999-12-18 15:32:46 +0000	[diff] [blame]	1506	<h3>1.8.1: Dec 18 1999</h3>
				1507	<ul>
				1508	<li>various patches to avoid troubles when using libxml with C++ compilers
				1509	the "namespace" keyword and C escaping in include files</li>
				1510	<li>a problem in one of the core macros IS_CHAR was corrected</li>
				1511	<li>fixed a bug introduced in 1.8.0 breaking default namespace processing,
				1512	and more specifically the Dia application</li>
Daniel Veillard	944b5ff	1999-12-15 19:08:24 +0000	[diff] [blame]	1513	<li>fixed a posteriori validation (validation after parsing, or by using a
				1514	Dtd not specified in the original document)</li>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	1515	<li>fixed a bug in</li>
Daniel Veillard	10a2c65	1999-12-12 13:03:50 +0000	[diff] [blame]	1516	</ul>
				1517
				1518	<h3>1.8.0: Dec 12 1999</h3>
				1519	<ul>
				1520	<li>cleanup, especially memory wise</li>
				1521	<li>the parser should be more reliable, especially the HTML one, it should
				1522	not crash, whatever the input !</li>
				1523	<li>Integrated various patches, especially a speedup improvement for large
				1524	dataset from <a href="mailto:cnygard@bellatlantic.net">Carl Nygard</a>,
				1525	configure with --with-buffers to enable them.</li>
				1526	<li>attribute normalization, oops should have been added long ago !</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1527	<li>attributes defaulted from DTDs should be available, xmlSetProp() now
				1528	does entities escaping by default.</li>
Daniel Veillard	4c3a203	1999-11-19 17:46:26 +0000	[diff] [blame]	1529	</ul>
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1530
				1531	<h3>1.7.4: Oct 25 1999</h3>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1532	<ul>
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1533	<li>Lots of HTML improvement</li>
				1534	<li>Fixed some errors when saving both XML and HTML</li>
				1535	<li>More examples, the regression tests should now look clean</li>
				1536	<li>Fixed a bug with contiguous charref</li>
				1537	</ul>
				1538
				1539	<h3>1.7.3: Sep 29 1999</h3>
				1540	<ul>
				1541	<li>portability problems fixed</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1542	<li>snprintf was used unconditionally, leading to link problems on system
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	1543	were it's not available, fixed</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1544	</ul>
				1545
				1546	<h3>1.7.1: Sep 24 1999</h3>
				1547	<ul>
				1548	<li>The basic type for strings manipulated by libxml has been renamed in
				1549	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]	1550	is that CHAR was conflicting with a predefined type on Windows. However
				1551	on non WIN32 environment, compatibility is provided by the way of a
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1552	<strong>#define </strong>.</li>
				1553	<li>Changed another error : the use of a structure field called errno, and
				1554	leading to troubles on platforms where it's a macro</li>
				1555	</ul>
				1556
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1557	<h3>1.7.0: Sep 23 1999</h3>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1558	<ul>
				1559	<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]	1560	href="html/libxml-nanohttp.html">nanohttp</a> module.</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1561	<li>Added an errno to report errors by another mean than a simple printf
				1562	like callback</li>
				1563	<li>Finished ID/IDREF support and checking when validation</li>
				1564	<li>Serious memory leaks fixed (there is now a <a
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	1565	href="html/libxml-xmlmemory.html">memory wrapper</a> module)</li>
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1566	<li>Improvement of <a href="http://www.w3.org/TR/xpath">XPath</a>
				1567	implementation</li>
				1568	<li>Added an HTML parser front-end</li>
				1569	</ul>
				1570
				1571	<h2><a name="XML">XML</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	1572
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	1573	<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]	1574	markup-based structured documents. Here is <a name="example">an example XML
				1575	document</a>:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	1576	<pre><?xml version="1.0"?>
				1577	<EXAMPLE prop1="gnome is great" prop2="&amp; linux too">
				1578	<head>
				1579	<title>Welcome to Gnome</title>
				1580	</head>
				1581	<chapter>
				1582	<title>The Linux adventure</title>
				1583	<p>bla bla bla ...</p>
				1584	<image href="linus.gif"/>
				1585	<p>...</p>
				1586	</chapter>
				1587	</EXAMPLE></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	1588
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1589	<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]	1590	information about its encoding. Then the rest of the document is a text
				1591	format whose structure is specified by tags between brackets. <strong>Each
				1592	tag opened has to be closed</strong>. XML is pedantic about this. However, if
				1593	a tag is empty (no content), a single tag can serve as both the opening and
				1594	closing tag if it ends with <code>/></code> rather than with
				1595	<code>></code>. Note that, for example, the image tag has no content (just
				1596	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]	1597
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1598	<p>XML can be applied successfully to a wide range of tasks, ranging from
				1599	long term structured document maintenance (where it follows the steps of
				1600	SGML) to simple data encoding mechanisms like configuration file formatting
				1601	(glade), spreadsheets (gnumeric), or even shorter lived documents such as
				1602	WebDAV where it is used to encode remote calls between a client and a
				1603	server.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	1604
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1605	<h2><a name="XSLT">XSLT</a></h2>
				1606
Daniel Veillard	6e6a6cc	2001-02-15 15:55:44 +0000	[diff] [blame]	1607	<p>Check <a href="http://xmlsoft.org/XSLT">the separate libxslt page</a></p>
				1608
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1609	<p><a href="http://www.w3.org/TR/xslt">XSL Transformations</a>, is a
				1610	language for transforming XML documents into other XML documents (or
				1611	HTML/textual output).</p>
Daniel Veillard	8268716	2001-01-22 15:32:01 +0000	[diff] [blame]	1612
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1613	<p>A separate library called libxslt is being developed on top of libxml2.
				1614	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]	1615
Daniel Veillard	383b147	2001-01-23 11:39:52 +0000	[diff] [blame]	1616	<p>You can check the <a
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	1617	href="http://cvs.gnome.org/lxr/source/libxslt/FEATURES">features</a>
				1618	supported and the progresses on the <a
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1619	href="http://cvs.gnome.org/lxr/source/libxslt/ChangeLog"
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1620	name="Changelog">Changelog</a>.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1621
				1622	<h2><a name="Python">Python and bindings</a></h2>
				1623
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	1624	<p>There are a number of language bindings and wrappers available for
				1625	libxml2, the list below is not exhaustive. Please contact the <a
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1626	href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
				1627	(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
				1628	order to get updates to this list or to discuss the specific topic of libxml2
				1629	or libxslt wrappers or bindings:</p>
				1630	<ul>
Daniel Veillard	c14401e	2002-11-20 14:28:17 +0000	[diff] [blame]	1631	<li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
				1632	most up-to-date C++ bindings for libxml2, check the <a
				1633	href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
				1634	and the <a
				1635	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]	1636	<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]	1637	based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
Daniel Veillard	9b6fd30	2002-05-13 12:06:47 +0000	[diff] [blame]	1638	<li>and a third C++ wrapper by Peter Jones <pjones@pmade.org>
				1639	<p>Website: <a
				1640	href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p>
				1641	</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1642	<li><a
				1643	href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1644	Sergeant</a> developed <a
				1645	href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1646	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]	1647	application server</a>.</li>
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	1648	<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]	1649	earlier version of the libxml/libxslt <a
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1650	href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	1651	<li>Gopal.V and Peter Minten develop <a
				1652	href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1653	C# libxml2 bindings.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1654	<li>Petr Kozelka provides <a
				1655	href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1656	libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
Daniel Veillard	b2fb8ed	2002-04-01 09:33:12 +0000	[diff] [blame]	1657	<li>Uwe Fechner also provides <a
				1658	href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1659	implementation for Kylix2/D5/D6 from Borland.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1660	<li>Wai-Sun "Squidster" Chia provides <a
				1661	href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
				1662	libxml2 bindings are also available in Ruby through the <a
				1663	href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
				1664	maintained by Tobias Peters.</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1665	<li>Steve Ball and contributors maintains <a
				1666	href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1667	Tcl</a>.</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1668	<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]	1669	<li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	1670	an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and
				1671	libxslt as part of GNU ClasspathX project.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1672	</ul>
				1673
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1674	<p>The distribution includes a set of Python bindings, which are guaranteed
				1675	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]	1676	interface have not yet reached the completeness of the C API.</p>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1677
Daniel Veillard	27907c7	2002-12-16 16:05:58 +0000	[diff] [blame]	1678	<p><a href="mailto:stephane.bidoul@softwareag.com">Stéphane Bidoul</a>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1679	maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows port
				1680	of the Python bindings</a>.</p>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1681
Daniel Veillard	7ef0fcb	2002-12-14 10:38:55 +0000	[diff] [blame]	1682	<p>Note to people interested in building bindings, the API is formalized as
				1683	<a href="libxml2-api.xml">an XML API description file</a> which allows to
				1684	automate a large part of the Python bindings, this includes function
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	1685	descriptions, enums, structures, typedefs, etc... The Python script used to
				1686	build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillard	7ef0fcb	2002-12-14 10:38:55 +0000	[diff] [blame]	1687
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1688	<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard	0b79dfe	2002-02-23 13:02:31 +0000	[diff] [blame]	1689	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1690	<li>If you use an RPM based distribution, simply install the <a
				1691	href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
				1692	RPM</a> (and if needed the <a
				1693	href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
				1694	RPM</a>).</li>
				1695	<li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
				1696	module distribution</a> corresponding to your installed version of
				1697	libxml2 and libxslt. Note that to install it you will need both libxml2
				1698	and libxslt installed and run "python setup.py build install" in the
				1699	module tree.</li>
Daniel Veillard	0b79dfe	2002-02-23 13:02:31 +0000	[diff] [blame]	1700	</ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1701
				1702	<p>The distribution includes a set of examples and regression tests for the
				1703	python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1704	excerpts from those tests:</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1705
				1706	<h3>tst.py:</h3>
				1707
				1708	<p>This is a basic test of the file interface and DOM navigation:</p>
				1709	<pre>import libxml2
				1710
				1711	doc = libxml2.parseFile("tst.xml")
				1712	if doc.name != "tst.xml":
				1713	print "doc.name failed"
				1714	sys.exit(1)
				1715	root = doc.children
				1716	if root.name != "doc":
				1717	print "root.name failed"
				1718	sys.exit(1)
				1719	child = root.children
				1720	if child.name != "foo":
				1721	print "child.name failed"
				1722	sys.exit(1)
				1723	doc.freeDoc()</pre>
				1724
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	1725	<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1726	xmlParseFile (most of the bindings are automatically generated, and the xml
				1727	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]	1728	binding level share the same subset of accessors:</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1729	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1730	<li><code>name</code> : returns the node name</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	1731	<li><code>type</code> : returns a string indicating the node type</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1732	<li><code>content</code> : returns the content of the node, it is based on
				1733	xmlNodeGetContent() and hence is recursive.</li>
				1734	<li><code>parent</code> , <code>children</code>, <code>last</code>,
				1735	<code>next</code>, <code>prev</code>, <code>doc</code>,
				1736	<code>properties</code>: pointing to the associated element in the tree,
				1737	those may return None in case no such link exists.</li>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1738	</ul>
				1739
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1740	<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1741	Reference counting for libxml2 trees would need quite a lot of work to
				1742	function properly, and rather than risk memory leaks if not implemented
				1743	correctly it sounds safer to have an explicit function to free a tree. The
				1744	wrapper python objects like doc, root or child are them automatically garbage
				1745	collected.</p>
				1746
				1747	<h3>validate.py:</h3>
				1748
				1749	<p>This test check the validation interfaces and redirection of error
				1750	messages:</p>
				1751	<pre>import libxml2
				1752
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1753	#deactivate error messages from the validation
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1754	def noerr(ctx, str):
				1755	pass
				1756
				1757	libxml2.registerErrorHandler(noerr, None)
				1758
				1759	ctxt = libxml2.createFileParserCtxt("invalid.xml")
				1760	ctxt.validate(1)
				1761	ctxt.parseDocument()
				1762	doc = ctxt.doc()
				1763	valid = ctxt.isValid()
				1764	doc.freeDoc()
				1765	if valid != 0:
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1766	print "validity check failed"</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1767
				1768	<p>The first thing to notice is the call to registerErrorHandler(), it
				1769	defines a new error handler global to the library. It is used to avoid seeing
				1770	the error messages when trying to validate the invalid document.</p>
				1771
				1772	<p>The main interest of that test is the creation of a parser context with
				1773	createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1774	parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1775	are also available using context methods.</p>
				1776
				1777	<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
				1778	C function interfaces in terms of objects method as much as possible. The
				1779	best to get a complete view of what methods are supported is to look at the
				1780	libxml2.py module containing all the wrappers.</p>
				1781
				1782	<h3>push.py:</h3>
				1783
				1784	<p>This test show how to activate the push parser interface:</p>
				1785	<pre>import libxml2
				1786
				1787	ctxt = libxml2.createPushParser(None, "<foo", 4, "test.xml")
				1788	ctxt.parseChunk("/>", 2, 1)
				1789	doc = ctxt.doc()
				1790
				1791	doc.freeDoc()</pre>
				1792
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1793	<p>The context is created with a special call based on the
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1794	xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1795	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]	1796	the resource in case URI-References need to be computed by the parser.</p>
				1797
				1798	<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]	1799	setting the third argument terminate to 1.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1800
				1801	<h3>pushSAX.py:</h3>
				1802
				1803	<p>this test show the use of the event based parsing interfaces. In this case
				1804	the parser does not build a document, but provides callback information as
				1805	the parser makes progresses analyzing the data being provided:</p>
				1806	<pre>import libxml2
				1807	log = ""
				1808
				1809	class callback:
				1810	def startDocument(self):
				1811	global log
				1812	log = log + "startDocument:"
				1813
				1814	def endDocument(self):
				1815	global log
				1816	log = log + "endDocument:"
				1817
				1818	def startElement(self, tag, attrs):
				1819	global log
				1820	log = log + "startElement %s %s:" % (tag, attrs)
				1821
				1822	def endElement(self, tag):
				1823	global log
				1824	log = log + "endElement %s:" % (tag)
				1825
				1826	def characters(self, data):
				1827	global log
				1828	log = log + "characters: %s:" % (data)
				1829
				1830	def warning(self, msg):
				1831	global log
				1832	log = log + "warning: %s:" % (msg)
				1833
				1834	def error(self, msg):
				1835	global log
				1836	log = log + "error: %s:" % (msg)
				1837
				1838	def fatalError(self, msg):
				1839	global log
				1840	log = log + "fatalError: %s:" % (msg)
				1841
				1842	handler = callback()
				1843
				1844	ctxt = libxml2.createPushParser(handler, "<foo", 4, "test.xml")
				1845	chunk = " url='tst'>b"
				1846	ctxt.parseChunk(chunk, len(chunk), 0)
				1847	chunk = "ar</foo>"
				1848	ctxt.parseChunk(chunk, len(chunk), 1)
				1849
Daniel Veillard	fcbfa2d	2002-02-21 17:54:27 +0000	[diff] [blame]	1850	reference = "startDocument:startElement foo {'url': 'tst'}:" + \
				1851	"characters: bar:endElement foo:endDocument:"
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1852	if log != reference:
				1853	print "Error got: %s" % log
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1854	print "Expected: %s" % reference</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1855
				1856	<p>The key object in that test is the handler, it provides a number of entry
				1857	points which can be called by the parser as it makes progresses to indicate
				1858	the information set obtained. The full set of callback is larger than what
				1859	the callback class in that specific example implements (see the SAX
				1860	definition for a complete list). The wrapper will only call those supplied by
				1861	the object when activated. The startElement receives the names of the element
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1862	and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1863
				1864	<p>Also note that the reference string generated from the callback shows a
				1865	single character call even though the string "bar" is passed to the parser
				1866	from 2 different call to parseChunk()</p>
				1867
				1868	<h3>xpath.py:</h3>
				1869
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1870	<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1871	<pre>import libxml2
				1872
				1873	doc = libxml2.parseFile("tst.xml")
				1874	ctxt = doc.xpathNewContext()
				1875	res = ctxt.xpathEval("//*")
				1876	if len(res) != 2:
				1877	print "xpath query: wrong node set size"
				1878	sys.exit(1)
				1879	if res[0].name != "doc" or res[1].name != "foo":
				1880	print "xpath query: wrong node set value"
				1881	sys.exit(1)
				1882	doc.freeDoc()
				1883	ctxt.xpathFreeContext()</pre>
				1884
				1885	<p>This test parses a file, then create an XPath context to evaluate XPath
				1886	expression on it. The xpathEval() method execute an XPath query and returns
				1887	the result mapped in a Python way. String and numbers are natively converted,
				1888	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]	1889	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]	1890	the result of the XPath query may point back to the document tree and hence
				1891	the document must be freed after the result of the query is used.</p>
				1892
				1893	<h3>xpathext.py:</h3>
				1894
				1895	<p>This test shows how to extend the XPath engine with functions written in
				1896	python:</p>
				1897	<pre>import libxml2
				1898
				1899	def foo(ctx, x):
				1900	return x + 1
				1901
				1902	doc = libxml2.parseFile("tst.xml")
				1903	ctxt = doc.xpathNewContext()
				1904	libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)
				1905	res = ctxt.xpathEval("foo(1)")
				1906	if res != 2:
				1907	print "xpath extension failure"
				1908	doc.freeDoc()
				1909	ctxt.xpathFreeContext()</pre>
				1910
				1911	<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]	1912	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]	1913
				1914	<h3>tstxpath.py:</h3>
				1915
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1916	<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]	1917	function can access the XPath evaluation context:</p>
				1918	<pre>def foo(ctx, x):
				1919	global called
				1920
				1921	#
				1922	# test that access to the XPath evaluation contexts
				1923	#
				1924	pctxt = libxml2.xpathParserContext(_obj=ctx)
				1925	ctxt = pctxt.context()
				1926	called = ctxt.function()
				1927	return x + 1</pre>
				1928
				1929	<p>All the interfaces around the XPath parser(or rather evaluation) context
				1930	are not finalized, but it should be sufficient to do contextual work at the
				1931	evaluation point.</p>
				1932
				1933	<h3>Memory debugging:</h3>
				1934
				1935	<p>last but not least, all tests starts with the following prologue:</p>
				1936	<pre>#memory debug specific
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	1937	libxml2.debugMemory(1)</pre>
Daniel Veillard	6dbcaf8	2002-02-20 14:37:47 +0000	[diff] [blame]	1938
				1939	<p>and ends with the following epilogue:</p>
				1940	<pre>#memory debug specific
				1941	libxml2.cleanupParser()
				1942	if libxml2.debugMemory(1) == 0:
				1943	print "OK"
				1944	else:
				1945	print "Memory leak %d bytes" % (libxml2.debugMemory(1))
				1946	libxml2.dumpMemory()</pre>
				1947
				1948	<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	1949	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]	1950	library state and checks that all allocated memory has been freed. If not it
				1951	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]	1952
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	1953	<h2><a name="architecture">libxml architecture</a></h2>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1954
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	1955	<p>Libxml is made of multiple components; some of them are optional, and most
				1956	of the block interfaces are public. The main components are:</p>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1957	<ul>
				1958	<li>an Input/Output layer</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	1959	<li>FTP and HTTP client layers (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1960	<li>an Internationalization layer managing the encodings support</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	1961	<li>a URI module</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1962	<li>the XML parser and its basic SAX interface</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	1963	<li>an HTML parser using the same SAX interface (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1964	<li>a SAX tree module to build an in-memory DOM representation</li>
				1965	<li>a tree module to manipulate the DOM representation</li>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	1966	<li>a validation module using the DOM representation (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1967	<li>an XPath module for global lookup in a DOM representation
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	1968	(optional)</li>
				1969	<li>a debug module (optional)</li>
Daniel Veillard	4540be4	2000-08-19 16:40:28 +0000	[diff] [blame]	1970	</ul>
				1971
				1972	<p>Graphically this gives the following:</p>
				1973
				1974	<p><img src="libxml.gif" alt="a graphical view of the various"></p>
				1975
				1976	<p></p>
				1977
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	1978	<h2><a name="tree">The tree output</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	1979
				1980	<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]	1981	returned is an <strong>xmlDocPtr</strong> (i.e., a pointer to an
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1982	<strong>xmlDoc</strong> structure). This structure contains information such
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	1983	as the file name, the document type, and a <strong>children</strong> pointer
				1984	which is the root of the document (or more exactly the first child under the
				1985	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]	1986	chained in double-linked lists of siblings and with a children<->parent
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	1987	relationship. An xmlNode can also carry properties (a chain of xmlAttr
				1988	structures). An attribute may have a value which is a list of TEXT or
				1989	ENTITY_REF nodes.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	1990
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	1991	<p>Here is an example (erroneous with respect to the XML spec since there
				1992	should be only one ELEMENT under the root):</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	1993
				1994	<p><img src="structure.gif" alt=" structure.gif "></p>
				1995
				1996	<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]	1997	called <strong>xmllint</strong> which parses XML files given as argument and
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	1998	prints them back as parsed. This is useful for detecting errors both in XML
				1999	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]	2000	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]	2001	result with the <a href="#example">example</a> given before:</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2002	<pre>DOCUMENT
				2003	version=1.0
				2004	standalone=true
				2005	ELEMENT EXAMPLE
				2006	ATTRIBUTE prop1
				2007	TEXT
				2008	content=gnome is great
				2009	ATTRIBUTE prop2
				2010	ENTITY_REF
				2011	TEXT
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	2012	content= linux too
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	2013	ELEMENT head
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2014	ELEMENT title
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2015	TEXT
				2016	content=Welcome to Gnome
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2017	ELEMENT chapter
				2018	ELEMENT title
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2019	TEXT
				2020	content=The Linux adventure
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2021	ELEMENT p
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2022	TEXT
				2023	content=bla bla bla ...
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	2024	ELEMENT image
				2025	ATTRIBUTE href
				2026	TEXT
				2027	content=linus.gif
				2028	ELEMENT p
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	2029	TEXT
				2030	content=...</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	2031
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2032	<p>This should be useful for learning the internal representation model.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	2033
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	2034	<h2><a name="interface">The SAX interface</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2035
Daniel Veillard	402e8c8	2000-02-29 22:57:47 +0000	[diff] [blame]	2036	<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]	2037	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]	2038	loaded using libxml), it's better to use the SAX interface of libxml. SAX is
				2039	a <strong>callback-based interface</strong> to the parser. Before parsing,
				2040	the application layer registers a customized set of callbacks which are
				2041	called by the library as it progresses through the XML input.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2042
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2043	<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]	2044	libxml, see the <a
				2045	href="http://www.daa.com.au/~james/gnome/xml-sax/xml-sax.html">nice
				2046	documentation</a>.written by <a href="mailto:james@daa.com.au">James
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2047	Henstridge</a>.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2048
				2049	<p>You can debug the SAX behaviour by using the <strong>testSAX</strong>
				2050	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]	2051	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]	2052	distribution). Here is the sequence of callbacks that would be reported by
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	2053	testSAX when parsing the example XML document shown earlier:</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2054	<pre>SAX.setDocumentLocator()
				2055	SAX.startDocument()
				2056	SAX.getEntity(amp)
				2057	SAX.startElement(EXAMPLE, prop1='gnome is great', prop2='&amp; linux too')
				2058	SAX.characters( , 3)
				2059	SAX.startElement(head)
				2060	SAX.characters( , 4)
				2061	SAX.startElement(title)
				2062	SAX.characters(Welcome to Gnome, 16)
				2063	SAX.endElement(title)
				2064	SAX.characters( , 3)
				2065	SAX.endElement(head)
				2066	SAX.characters( , 3)
				2067	SAX.startElement(chapter)
				2068	SAX.characters( , 4)
				2069	SAX.startElement(title)
				2070	SAX.characters(The Linux adventure, 19)
				2071	SAX.endElement(title)
				2072	SAX.characters( , 4)
				2073	SAX.startElement(p)
				2074	SAX.characters(bla bla bla ..., 15)
				2075	SAX.endElement(p)
				2076	SAX.characters( , 4)
				2077	SAX.startElement(image, href='linus.gif')
				2078	SAX.endElement(image)
				2079	SAX.characters( , 4)
				2080	SAX.startElement(p)
				2081	SAX.characters(..., 3)
				2082	SAX.endElement(p)
				2083	SAX.characters( , 3)
				2084	SAX.endElement(chapter)
				2085	SAX.characters( , 1)
				2086	SAX.endElement(EXAMPLE)
				2087	SAX.endDocument()</pre>
				2088
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	2089	<p>Most of the other interfaces of libxml are based on the DOM tree-building
				2090	facility, so nearly everything up to the end of this document presupposes the
				2091	use of the standard DOM tree build. Note that the DOM tree itself is built by
				2092	a set of registered default callbacks, without internal specific
				2093	interface.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	2094
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2095	<h2><a name="Validation">Validation & DTDs</a></h2>
				2096
				2097	<p>Table of Content:</p>
				2098	<ol>
				2099	<li><a href="#General5">General overview</a></li>
				2100	<li><a href="#definition">The definition</a></li>
				2101	<li><a href="#Simple">Simple rules</a>
				2102	<ol>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	2103	<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]	2104	<li><a href="#Declaring">Declaring elements</a></li>
				2105	<li><a href="#Declaring1">Declaring attributes</a></li>
				2106	</ol>
				2107	</li>
				2108	<li><a href="#Some">Some examples</a></li>
				2109	<li><a href="#validate">How to validate</a></li>
				2110	<li><a href="#Other">Other resources</a></li>
				2111	</ol>
				2112
				2113	<h3><a name="General5">General overview</a></h3>
				2114
				2115	<p>Well what is validation and what is a DTD ?</p>
				2116
				2117	<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]	2118	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]	2119	specification, and allows one to describe and verify that a given document
				2120	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]	2121
				2122	<p>Validation is the process of checking a document against a DTD (more
				2123	generally against a set of construction rules).</p>
				2124
				2125	<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]	2126	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]	2127	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]	2128	(by defining the allowed content of an element; either text, a regular
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2129	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]	2130	and children). The DTD also defines the valid attributes for all elements and
				2131	the types of those attributes.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2132
				2133	<h3><a name="definition1">The definition</a></h3>
				2134
				2135	<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
				2136	href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
				2137	Rev1</a>):</p>
				2138	<ul>
				2139	<li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
				2140	elements</a></li>
				2141	<li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
				2142	attributes</a></li>
				2143	</ul>
				2144
				2145	<p>(unfortunately) all this is inherited from the SGML world, the syntax is
				2146	ancient...</p>
				2147
				2148	<h3><a name="Simple1">Simple rules</a></h3>
				2149
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2150	<p>Writing DTDs can be done in many ways. The rules to build them if you need
				2151	something permanent or something which can evolve over time can be radically
				2152	different. Really complex DTDs like DocBook ones are flexible but quite
				2153	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]	2154	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]	2155	usable for complex DTD design.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2156
				2157	<h4><a name="reference1">How to reference a DTD from a document</a>:</h4>
				2158
				2159	<p>Assuming the top element of the document is <code>spec</code> and the dtd
				2160	is placed in the file <code>mydtd</code> in the subdirectory
				2161	<code>dtds</code> of the directory from where the document were loaded:</p>
				2162
				2163	<p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p>
				2164
				2165	<p>Notes:</p>
				2166	<ul>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2167	<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]	2168	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]	2169	full URL string indicating the location of your DTD on the Web. This is a
				2170	really good thing to do if you want others to validate your document.</li>
				2171	<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]	2172	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]	2173	without having to locate it on the web.</li>
				2174	<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]	2175	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]	2176	told to the parser/validator as the first element of the
				2177	<code>DOCTYPE</code> declaration.</li>
				2178	</ul>
				2179
				2180	<h4><a name="Declaring2">Declaring elements</a>:</h4>
				2181
				2182	<p>The following declares an element <code>spec</code>:</p>
				2183
				2184	<p><code><!ELEMENT spec (front, body, back?)></code></p>
				2185
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2186	<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]	2187	one <code>body</code> and one optional <code>back</code> children elements in
				2188	this order. The declaration of one element of the structure and its content
				2189	are done in a single declaration. Similarly the following declares
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2190	<code>div1</code> elements:</p>
				2191
Daniel Veillard	5173727	2002-01-23 23:10:38 +0000	[diff] [blame]	2192	<p><code><!ELEMENT div1 (head, (p \| list \| note)*, div2?)></code></p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2193
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2194	<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]	2195	<code>p</code>, <code>list</code>s and <code>note</code>s and then an
				2196	optional <code>div2</code>. And last but not least an element can contain
				2197	text:</p>
				2198
				2199	<p><code><!ELEMENT b (#PCDATA)></code></p>
				2200
				2201	<p><code>b</code> contains text or being of mixed content (text and elements
				2202	in no particular order):</p>
				2203
				2204	<p><code><!ELEMENT p (#PCDATA\|a\|ul\|b\|i\|em)*></code></p>
				2205
				2206	<p><code>p </code>can contain text or <code>a</code>, <code>ul</code>,
				2207	<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
				2208	order.</p>
				2209
				2210	<h4><a name="Declaring1">Declaring attributes</a>:</h4>
				2211
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2212	<p>Again the attributes declaration includes their content definition:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2213
				2214	<p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p>
				2215
				2216	<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]	2217	attribute containing text (<code>CDATA</code>) and which is optional
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2218	(<code>#IMPLIED</code>). The attribute value can also be defined within a
				2219	set:</p>
				2220
				2221	<p><code><!ATTLIST list type (bullets\|ordered\|glossary)
				2222	"ordered"></code></p>
				2223
				2224	<p>means <code>list</code> element have a <code>type</code> attribute with 3
				2225	allowed values "bullets", "ordered" or "glossary" and which default to
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2226	"ordered" if the attribute is not explicitly specified.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2227
				2228	<p>The content type of an attribute can be text (<code>CDATA</code>),
				2229	anchor/reference/references
				2230	(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
				2231	(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
				2232	(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
				2233	<code>chapter</code> element can have an optional <code>id</code> attribute
				2234	of type <code>ID</code>, usable for reference from attribute of type
				2235	IDREF:</p>
				2236
				2237	<p><code><!ATTLIST chapter id ID #IMPLIED></code></p>
				2238
				2239	<p>The last value of an attribute definition can be <code>#REQUIRED
				2240	</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
				2241	meaning that it is optional, or the default value (possibly prefixed by
				2242	<code>#FIXED</code> if it is the only allowed).</p>
				2243
				2244	<p>Notes:</p>
				2245	<ul>
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2246	<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]	2247	single expression, but it is just a convention adopted by a lot of DTD
				2248	writers:
				2249	<pre><!ATTLIST termdef
				2250	id ID #REQUIRED
				2251	name CDATA #IMPLIED></pre>
				2252	<p>The previous construct defines both <code>id</code> and
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2253	<code>name</code> attributes for the element <code>termdef</code>.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2254	</li>
				2255	</ul>
				2256
				2257	<h3><a name="Some1">Some examples</a></h3>
				2258
				2259	<p>The directory <code>test/valid/dtds/</code> in the libxml distribution
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2260	contains some complex DTD examples. The example in the file
				2261	<code>test/valid/dia.xml</code> shows an XML file where the simple DTD is
				2262	directly included within the document.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2263
				2264	<h3><a name="validate1">How to validate</a></h3>
				2265
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2266	<p>The simplest way is to use the xmllint program included with libxml. The
				2267	<code>--valid</code> option turns-on validation of the files given as input.
				2268	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]	2269	1.0 specification:</p>
				2270
				2271	<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
				2272
Daniel Veillard	0b28e88	2002-07-24 23:47:05 +0000	[diff] [blame]	2273	<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]	2274
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2275	<p>The <code>--dtdvalid dtd</code> allows validation of the document(s)
				2276	against a given DTD.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2277
				2278	<p>Libxml exports an API to handle DTDs and validation, check the <a
				2279	href="http://xmlsoft.org/html/libxml-valid.html">associated
				2280	description</a>.</p>
				2281
				2282	<h3><a name="Other1">Other resources</a></h3>
				2283
				2284	<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
				2285	will just list one for now, others pointers welcome:</p>
				2286	<ul>
				2287	<li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
				2288	</ul>
				2289
				2290	<p>I suggest looking at the examples found under test/valid/dtd and any of
				2291	the large number of books available on XML. The dia example in test/valid
				2292	should be both simple and complete enough to allow you to build your own.</p>
				2293
				2294	<p></p>
				2295
				2296	<h2><a name="Memory">Memory Management</a></h2>
				2297
				2298	<p>Table of Content:</p>
				2299	<ol>
				2300	<li><a href="#General3">General overview</a></li>
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	2301	<li><a href="#setting">Setting libxml set of memory routines</a></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2302	<li><a href="#cleanup">Cleaning up after parsing</a></li>
				2303	<li><a href="#Debugging">Debugging routines</a></li>
				2304	<li><a href="#General4">General memory requirements</a></li>
				2305	</ol>
				2306
				2307	<h3><a name="General3">General overview</a></h3>
				2308
				2309	<p>The module <code><a
				2310	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlmemory.h</a></code>
				2311	provides the interfaces to the libxml memory system:</p>
				2312	<ul>
				2313	<li>libxml does not use the libc memory allocator directly but xmlFree(),
				2314	xmlMalloc() and xmlRealloc()</li>
				2315	<li>those routines can be reallocated to a specific set of routine, by
				2316	default the libc ones i.e. free(), malloc() and realloc()</li>
				2317	<li>the xmlmemory.c module includes a set of debugging routine</li>
				2318	</ul>
				2319
				2320	<h3><a name="setting">Setting libxml set of memory routines</a></h3>
				2321
				2322	<p>It is sometimes useful to not use the default memory allocator, either for
				2323	debugging, analysis or to implement a specific behaviour on memory management
				2324	(like on embedded systems). Two function calls are available to do so:</p>
				2325	<ul>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2326	<li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemGet
				2327	()</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]	2328	<li><a
				2329	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemSetup()</a>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2330	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]	2331	</ul>
				2332
				2333	<p>Of course a call to xmlMemSetup() should probably be done before calling
				2334	any other libxml routines (unless you are sure your allocations routines are
				2335	compatibles).</p>
				2336
				2337	<h3><a name="cleanup">Cleaning up after parsing</a></h3>
				2338
				2339	<p>Libxml is not stateless, there is a few set of memory structures needing
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2340	allocation before the parser is fully functional (some encoding structures
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2341	for example). This also mean that once parsing is finished there is a tiny
				2342	amount of memory (a few hundred bytes) which can be recollected if you don't
				2343	reuse the parser immediately:</p>
				2344	<ul>
				2345	<li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlCleanupParser
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2346	()</a> is a centralized routine to free the parsing states. Note that it
				2347	won't deallocate any produced tree if any (use the xmlFreeDoc() and
				2348	related routines for this).</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2349	<li><a href="http://xmlsoft.org/html/libxml-parser.html">xmlInitParser
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2350	()</a> is the dual routine allowing to preallocate the parsing state
				2351	which can be useful for example to avoid initialization reentrancy
				2352	problems when using libxml in multithreaded applications</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2353	</ul>
				2354
				2355	<p>Generally xmlCleanupParser() is safe, if needed the state will be rebuild
				2356	at the next invocation of parser routines, but be careful of the consequences
				2357	in multithreaded applications.</p>
				2358
				2359	<h3><a name="Debugging">Debugging routines</a></h3>
				2360
				2361	<p>When configured using --with-mem-debug flag (off by default), libxml uses
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2362	a set of memory allocation debugging routines keeping track of all allocated
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2363	blocks and the location in the code where the routine was called. A couple of
				2364	other debugging routines allow to dump the memory allocated infos to a file
				2365	or call a specific routine when a given block number is allocated:</p>
				2366	<ul>
				2367	<li><a
				2368	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMallocLoc()</a>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2369	<a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2370	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlReallocLoc()</a>
				2371	and <a
				2372	href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemStrdupLoc()</a>
				2373	are the memory debugging replacement allocation routines</li>
				2374	<li><a href="http://xmlsoft.org/html/libxml-xmlmemory.html">xmlMemoryDump
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	2375	()</a> dumps all the informations about the allocated memory block lefts
				2376	in the <code>.memdump</code> file</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2377	</ul>
				2378
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2379	<p>When developing libxml memory debug is enabled, the tests programs call
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2380	xmlMemoryDump () and the "make test" regression tests will check for any
				2381	memory leak during the full regression test sequence, this helps a lot
				2382	ensuring that libxml does not leak memory and bullet proof memory
				2383	allocations use (some libc implementations are known to be far too permissive
				2384	resulting in major portability problems!).</p>
				2385
				2386	<p>If the .memdump reports a leak, it displays the allocation function and
				2387	also tries to give some informations about the content and structure of the
				2388	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]	2389	but not always. Assuming the allocation problem is reproducible, it is
				2390	possible to find more easily:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2391	<ol>
				2392	<li>write down the block number xxxx not allocated</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2393	<li>export the environment variable XML_MEM_BREAKPOINT=xxxx , the easiest
Daniel Veillard	7579482	2002-04-11 16:24:32 +0000	[diff] [blame]	2394	when using GDB is to simply give the command
				2395	<p><code>set environment XML_MEM_BREAKPOINT xxxx</code></p>
				2396	<p>before running the program.</p>
				2397	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2398	<li>run the program under a debugger and set a breakpoint on
				2399	xmlMallocBreakpoint() a specific function called when this precise block
				2400	is allocated</li>
				2401	<li>when the breakpoint is reached you can then do a fine analysis of the
				2402	allocation an step to see the condition resulting in the missing
				2403	deallocation.</li>
				2404	</ol>
				2405
				2406	<p>I used to use a commercial tool to debug libxml memory problems but after
				2407	noticing that it was not detecting memory leaks that simple mechanism was
Daniel Veillard	7579482	2002-04-11 16:24:32 +0000	[diff] [blame]	2408	used and proved extremely efficient until now. Lately I have also used <a
				2409	href="http://developer.kde.org/~sewardj/">valgrind</a> with quite some
				2410	success, it is tied to the i386 architecture since it works by emulating the
				2411	processor and instruction set, it is slow but extremely efficient, i.e. it
				2412	spot memory usage errors in a very precise way.</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2413
				2414	<h3><a name="General4">General memory requirements</a></h3>
				2415
				2416	<p>How much libxml memory require ? It's hard to tell in average it depends
				2417	of a number of things:</p>
				2418	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2419	<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]	2420	information maintained about the stacks of names and entities locations.
				2421	The I/O and encoding handlers will probably account for a few KBytes.
				2422	This is true for both the XML and HTML parser (though the HTML parser
				2423	need more state).</li>
				2424	<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]	2425	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]	2426	textual document the internal memory requirement is about 4 times the
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2427	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]	2428	recommendation is a bit more of 150KBytes and takes 650KBytes of main
				2429	memory when parsed). Validation will add a amount of memory required for
				2430	maintaining the external Dtd state which should be linear with the
				2431	complexity of the content model defined by the Dtd</li>
				2432	<li>If you don't care about the advanced features of libxml like
				2433	validation, DOM, XPath or XPointer, but really need to work fixed memory
				2434	requirements, then the SAX interface should be used.</li>
				2435	</ul>
				2436
				2437	<p></p>
				2438
				2439	<h2><a name="Encodings">Encodings support</a></h2>
				2440
				2441	<p>Table of Content:</p>
				2442	<ol>
				2443	<li><a href="encoding.html#What">What does internationalization support
				2444	mean ?</a></li>
				2445	<li><a href="encoding.html#internal">The internal encoding, how and
				2446	why</a></li>
				2447	<li><a href="encoding.html#implemente">How is it implemented ?</a></li>
				2448	<li><a href="encoding.html#Default">Default supported encodings</a></li>
				2449	<li><a href="encoding.html#extend">How to extend the existing
				2450	support</a></li>
				2451	</ol>
				2452
				2453	<h3><a name="What">What does internationalization support mean ?</a></h3>
				2454
				2455	<p>XML was designed from the start to allow the support of any character set
				2456	by using Unicode. Any conformant XML parser has to support the UTF-8 and
				2457	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]	2458	is a variable length encoding whose greatest points are to reuse the same
				2459	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]	2460	more complex to handle in practice. UTF-16 use 2 bytes per characters (and
				2461	sometimes combines two pairs), it makes implementation easier, but looks a
				2462	bit overkill for Western languages encoding. Moreover the XML specification
				2463	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]	2464	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]	2465	document encoded in ISO-8859 1 and using accentuated letter that we French
				2466	likes for both markup and content:</p>
				2467	<pre><?xml version="1.0" encoding="ISO-8859-1"?>
				2468	<très>là</très></pre>
				2469
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2470	<p>Having internationalization support in libxml means the following:</p>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2471	<ul>
				2472	<li>the document is properly parsed</li>
				2473	<li>informations about it's encoding are saved</li>
				2474	<li>it can be modified</li>
				2475	<li>it can be saved in its original encoding</li>
				2476	<li>it can also be saved in another encoding supported by libxml (for
				2477	example straight UTF8 or even an ASCII form)</li>
				2478	</ul>
				2479
				2480	<p>Another very important point is that the whole libxml API, with the
				2481	exception of a few routines to read with a specific encoding or save to a
				2482	specific encoding, is completely agnostic about the original encoding of the
				2483	document.</p>
				2484
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2485	<p>It should be noted too that the HTML parser embedded in libxml now obey
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2486	the same rules too, the following document will be (as of 2.2.2) handled in
				2487	an internationalized fashion by libxml too:</p>
				2488	<pre><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
				2489	"http://www.w3.org/TR/REC-html40/loose.dtd">
				2490	<html lang="fr">
				2491	<head>
				2492	<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1">
				2493	</head>
				2494	<body>
				2495	<p>W3C crée des standards pour le Web.</body>
				2496	</html></pre>
				2497
				2498	<h3><a name="internal">The internal encoding, how and why</a></h3>
				2499
				2500	<p>One of the core decision was to force all documents to be converted to a
				2501	default internal encoding, and that encoding to be UTF-8, here are the
				2502	rationale for those choices:</p>
				2503	<ul>
				2504	<li>keeping the native encoding in the internal form would force the libxml
				2505	users (or the code associated) to be fully aware of the encoding of the
				2506	original document, for examples when adding a text node to a document,
				2507	the content would have to be provided in the document encoding, i.e. the
				2508	client code would have to check it before hand, make sure it's conformant
				2509	to the encoding, etc ... Very hard in practice, though in some specific
				2510	cases this may make sense.</li>
				2511	<li>the second decision was which encoding. From the XML spec only UTF8 and
				2512	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]	2513	is mandatory support. UCS-4 (32 bits fixed size encoding) could be
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2514	considered an intelligent choice too since it's a direct Unicode mapping
				2515	support. I selected UTF-8 on the basis of efficiency and compatibility
				2516	with surrounding software:
				2517	<ul>
				2518	<li>UTF-8 while a bit more complex to convert from/to (i.e. slightly
				2519	more costly to import and export CPU wise) is also far more compact
				2520	than UTF-16 (and UCS-4) for a majority of the documents I see it used
				2521	for right now (RPM RDF catalogs, advogato data, various configuration
				2522	file formats, etc.) and the key point for today's computer
				2523	architecture is efficient uses of caches. If one nearly double the
				2524	memory requirement to store the same amount of data, this will trash
				2525	caches (main memory/external caches/internal caches) and my take is
				2526	that this harms the system far more than the CPU requirements needed
				2527	for the conversion to UTF-8</li>
				2528	<li>Most of libxml version 1 users were using it with straight ASCII
				2529	most of the time, doing the conversion with an internal encoding
				2530	requiring all their code to be rewritten was a serious show-stopper
				2531	for using UTF-16 or UCS-4.</li>
				2532	<li>UTF-8 is being used as the de-facto internal encoding standard for
				2533	related code like the <a href="http://www.pango.org/">pango</a>
				2534	upcoming Gnome text widget, and a lot of Unix code (yep another place
				2535	where Unix programmer base takes a different approach from Microsoft
				2536	- they are using UTF-16)</li>
				2537	</ul>
				2538	</li>
				2539	</ul>
				2540
				2541	<p>What does this mean in practice for the libxml user:</p>
				2542	<ul>
				2543	<li>xmlChar, the libxml data type is a byte, those bytes must be assembled
				2544	as UTF-8 valid strings. The proper way to terminate an xmlChar * string
				2545	is simply to append 0 byte, as usual.</li>
				2546	<li>One just need to make sure that when using chars outside the ASCII set,
				2547	the values has been properly converted to UTF-8</li>
				2548	</ul>
				2549
				2550	<h3><a name="implemente">How is it implemented ?</a></h3>
				2551
				2552	<p>Let's describe how all this works within libxml, basically the I18N
				2553	(internationalization) support get triggered only during I/O operation, i.e.
				2554	when reading a document or saving one. Let's look first at the reading
				2555	sequence:</p>
				2556	<ol>
				2557	<li>when a document is processed, we usually don't know the encoding, a
				2558	simple heuristic allows to detect UTF-18 and UCS-4 from whose where the
				2559	ASCII range (0-0x7F) maps with ASCII</li>
				2560	<li>the xml declaration if available is parsed, including the encoding
				2561	declaration. At that point, if the autodetected encoding is different
				2562	from the one declared a call to xmlSwitchEncoding() is issued.</li>
				2563	<li>If there is no encoding declaration, then the input has to be in either
				2564	UTF-8 or UTF-16, if it is not then at some point when processing the
				2565	input, the converter/checker of UTF-8 form will raise an encoding error.
				2566	You may end-up with a garbled document, or no document at all ! Example:
				2567	<pre>~/XML -> ./xmllint err.xml
				2568	err.xml:1: error: Input is not proper UTF-8, indicate encoding !
				2569	<très>là</très>
				2570	^
				2571	err.xml:1: error: Bytes: 0xE8 0x73 0x3E 0x6C
				2572	<très>là</très>
				2573	^</pre>
				2574	</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2575	<li>xmlSwitchEncoding() does an encoding name lookup, canonicalize it, and
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2576	then search the default registered encoding converters for that encoding.
				2577	If it's not within the default set and iconv() support has been compiled
				2578	it, it will ask iconv for such an encoder. If this fails then the parser
				2579	will report an error and stops processing:
				2580	<pre>~/XML -> ./xmllint err2.xml
				2581	err2.xml:1: error: Unsupported encoding UnsupportedEnc
				2582	<?xml version="1.0" encoding="UnsupportedEnc"?>
				2583	^</pre>
				2584	</li>
Daniel Veillard	46c5c1d	2002-05-20 07:15:54 +0000	[diff] [blame]	2585	<li>From that point the encoder processes progressively the input (it is
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2586	plugged as a front-end to the I/O module) for that entity. It captures
				2587	and convert on-the-fly the document to be parsed to UTF-8. The parser
				2588	itself just does UTF-8 checking of this input and process it
				2589	transparently. The only difference is that the encoding information has
				2590	been added to the parsing context (more precisely to the input
				2591	corresponding to this entity).</li>
				2592	<li>The result (when using DOM) is an internal form completely in UTF-8
				2593	with just an encoding information on the document node.</li>
				2594	</ol>
				2595
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2596	<p>Ok then what happens when saving the document (assuming you
				2597	collected/built an xmlDoc DOM like structure) ? It depends on the function
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2598	called, xmlSaveFile() will just try to save in the original encoding, while
				2599	xmlSaveFileTo() and xmlSaveFileEnc() can optionally save to a given
				2600	encoding:</p>
				2601	<ol>
				2602	<li>if no encoding is given, libxml will look for an encoding value
				2603	associated to the document and if it exists will try to save to that
				2604	encoding,
				2605	<p>otherwise everything is written in the internal form, i.e. UTF-8</p>
				2606	</li>
				2607	<li>so if an encoding was specified, either at the API level or on the
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2608	document, libxml will again canonicalize the encoding name, lookup for a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2609	converter in the registered set or through iconv. If not found the
				2610	function will return an error code</li>
				2611	<li>the converter is placed before the I/O buffer layer, as another kind of
				2612	buffer, then libxml will simply push the UTF-8 serialization to through
				2613	that buffer, which will then progressively be converted and pushed onto
				2614	the I/O layer.</li>
				2615	<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]	2616	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]	2617	ISO-8859-1 converter won't work. Since the encoders are progressive they
				2618	will just report the error and the number of bytes converted, at that
				2619	point libxml will decode the offending character, remove it from the
				2620	buffer and replace it with the associated charRef encoding &#123; and
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2621	resume the conversion. This guarantees that any document will be saved
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2622	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]	2623	a problem in the current version, in practice avoid using non-ascii
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2624	characters for tags or attributes names @@). A special "ascii" encoding
				2625	name is used to save documents to a pure ascii form can be used when
				2626	portability is really crucial</li>
				2627	</ol>
				2628
				2629	<p>Here is a few examples based on the same test document:</p>
				2630	<pre>~/XML -> ./xmllint isolat1
				2631	<?xml version="1.0" encoding="ISO-8859-1"?>
				2632	<très>là</très>
				2633	~/XML -> ./xmllint --encode UTF-8 isolat1
				2634	<?xml version="1.0" encoding="UTF-8"?>
				2635	<trÃ¨s>lÃ </trÃ¨s>
				2636	~/XML -> </pre>
				2637
				2638	<p>The same processing is applied (and reuse most of the code) for HTML I18N
				2639	processing. Looking up and modifying the content encoding is a bit more
				2640	difficult since it is located in a <meta> tag under the <head>,
				2641	so a couple of functions htmlGetMetaEncoding() and htmlSetMetaEncoding() have
				2642	been provided. The parser also attempts to switch encoding on the fly when
				2643	detecting such a tag on input. Except for that the processing is the same
				2644	(and again reuses the same code).</p>
				2645
				2646	<h3><a name="Default">Default supported encodings</a></h3>
				2647
				2648	<p>libxml has a set of default converters for the following encodings
				2649	(located in encoding.c):</p>
				2650	<ol>
				2651	<li>UTF-8 is supported by default (null handlers)</li>
				2652	<li>UTF-16, both little and big endian</li>
				2653	<li>ISO-Latin-1 (ISO-8859-1) covering most western languages</li>
				2654	<li>ASCII, useful mostly for saving</li>
				2655	<li>HTML, a specific handler for the conversion of UTF-8 to ASCII with HTML
				2656	predefined entities like &copy; for the Copyright sign.</li>
				2657	</ol>
				2658
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2659	<p>More over when compiled on an Unix platform with iconv support the full
				2660	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]	2661	linux machine with glibc-2.1 the list of supported encodings and aliases fill
				2662	3 full pages, and include UCS-4, the full set of ISO-Latin encodings, and the
				2663	various Japanese ones.</p>
				2664
				2665	<h4>Encoding aliases</h4>
				2666
				2667	<p>From 2.2.3, libxml has support to register encoding names aliases. The
				2668	goal is to be able to parse document whose encoding is supported but where
				2669	the name differs (for example from the default set of names accepted by
				2670	iconv). The following functions allow to register and handle new aliases for
				2671	existing encodings. Once registered libxml will automatically lookup the
				2672	aliases when handling a document:</p>
				2673	<ul>
				2674	<li>int xmlAddEncodingAlias(const char name, const char alias);</li>
				2675	<li>int xmlDelEncodingAlias(const char *alias);</li>
				2676	<li>const char * xmlGetEncodingAlias(const char *alias);</li>
				2677	<li>void xmlCleanupEncodingAliases(void);</li>
				2678	</ul>
				2679
				2680	<h3><a name="extend">How to extend the existing support</a></h3>
				2681
				2682	<p>Well adding support for new encoding, or overriding one of the encoders
				2683	(assuming it is buggy) should not be hard, just write an input and output
				2684	conversion routines to/from UTF-8, and register them using
				2685	xmlNewCharEncodingHandler(name, xxxToUTF8, UTF8Toxxx), and they will be
				2686	called automatically if the parser(s) encounter such an encoding name
				2687	(register it uppercase, this will help). The description of the encoders,
				2688	their arguments and expected return values are described in the encoding.h
				2689	header.</p>
				2690
				2691	<p>A quick note on the topic of subverting the parser to use a different
				2692	internal encoding than UTF-8, in some case people will absolutely want to
				2693	keep the internal encoding different, I think it's still possible (but the
				2694	encoding must be compliant with ASCII on the same subrange) though I didn't
				2695	tried it. The key is to override the default conversion routines (by
				2696	registering null encoders/decoders for your charsets), and bypass the UTF-8
				2697	checking of the parser by setting the parser context charset
				2698	(ctxt->charset) to something different than XML_CHAR_ENCODING_UTF8, but
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2699	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]	2700	saving back.</p>
				2701
				2702	<p>Basically proper I18N support is important, this requires at least
				2703	libxml-2.0.0, but a lot of features and corrections are really available only
				2704	starting 2.2.</p>
				2705
				2706	<h2><a name="IO">I/O Interfaces</a></h2>
				2707
				2708	<p>Table of Content:</p>
				2709	<ol>
				2710	<li><a href="#General1">General overview</a></li>
				2711	<li><a href="#basic">The basic buffer type</a></li>
				2712	<li><a href="#Input">Input I/O handlers</a></li>
				2713	<li><a href="#Output">Output I/O handlers</a></li>
				2714	<li><a href="#entities">The entities loader</a></li>
				2715	<li><a href="#Example2">Example of customized I/O</a></li>
				2716	</ol>
				2717
				2718	<h3><a name="General1">General overview</a></h3>
				2719
				2720	<p>The module <code><a
				2721	href="http://xmlsoft.org/html/libxml-xmlio.html">xmlIO.h</a></code> provides
				2722	the interfaces to the libxml I/O system. This consists of 4 main parts:</p>
				2723	<ul>
				2724	<li>Entities loader, this is a routine which tries to fetch the entities
				2725	(files) based on their PUBLIC and SYSTEM identifiers. The default loader
				2726	don't look at the public identifier since libxml do not maintain a
				2727	catalog. You can redefine you own entity loader by using
				2728	<code>xmlGetExternalEntityLoader()</code> and
Daniel Veillard	9c46682	2001-10-25 12:03:39 +0000	[diff] [blame]	2729	<code>xmlSetExternalEntityLoader()</code>. <a href="#entities">Check the
				2730	example</a>.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2731	<li>Input I/O buffers which are a commodity structure used by the parser(s)
				2732	input layer to handle fetching the informations to feed the parser. This
				2733	provides buffering and is also a placeholder where the encoding
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	2734	converters to UTF8 are piggy-backed.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2735	<li>Output I/O buffers are similar to the Input ones and fulfill similar
				2736	task but when generating a serialization from a tree.</li>
				2737	<li>A mechanism to register sets of I/O callbacks and associate them with
				2738	specific naming schemes like the protocol part of the URIs.
				2739	<p>This affect the default I/O operations and allows to use specific I/O
				2740	handlers for certain names.</p>
				2741	</li>
				2742	</ul>
				2743
				2744	<p>The general mechanism used when loading http://rpmfind.net/xml.html for
				2745	example in the HTML parser is the following:</p>
				2746	<ol>
				2747	<li>The default entity loader calls <code>xmlNewInputFromFile()</code> with
				2748	the parsing context and the URI string.</li>
				2749	<li>the URI string is checked against the existing registered handlers
				2750	using their match() callback function, if the HTTP module was compiled
				2751	in, it is registered and its match() function will succeeds</li>
				2752	<li>the open() function of the handler is called and if successful will
				2753	return an I/O Input buffer</li>
				2754	<li>the parser will the start reading from this buffer and progressively
				2755	fetch information from the resource, calling the read() function of the
				2756	handler until the resource is exhausted</li>
				2757	<li>if an encoding change is detected it will be installed on the input
				2758	buffer, providing buffering and efficient use of the conversion
				2759	routines</li>
				2760	<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]	2761	called once and the Input buffer and associated resources are
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2762	deallocated.</li>
				2763	</ol>
				2764
				2765	<p>The user defined callbacks are checked first to allow overriding of the
				2766	default libxml I/O routines.</p>
				2767
				2768	<h3><a name="basic">The basic buffer type</a></h3>
				2769
				2770	<p>All the buffer manipulation handling is done using the
				2771	<code>xmlBuffer</code> type define in <code><a
				2772	href="http://xmlsoft.org/html/libxml-tree.html">tree.h</a> </code>which is a
				2773	resizable memory buffer. The buffer allocation strategy can be selected to be
				2774	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]	2775	trade-off). The values are <code>XML_BUFFER_ALLOC_EXACT</code> and
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2776	<code>XML_BUFFER_ALLOC_DOUBLEIT</code>, and can be set individually or on a
				2777	system wide basis using <code>xmlBufferSetAllocationScheme()</code>. A number
				2778	of functions allows to manipulate buffers with names starting with the
				2779	<code>xmlBuffer...</code> prefix.</p>
				2780
				2781	<h3><a name="Input">Input I/O handlers</a></h3>
				2782
				2783	<p>An Input I/O handler is a simple structure
				2784	<code>xmlParserInputBuffer</code> containing a context associated to the
				2785	resource (file descriptor, or pointer to a protocol handler), the read() and
				2786	close() callbacks to use and an xmlBuffer. And extra xmlBuffer and a charset
				2787	encoding handler are also present to support charset conversion when
				2788	needed.</p>
				2789
				2790	<h3><a name="Output">Output I/O handlers</a></h3>
				2791
				2792	<p>An Output handler <code>xmlOutputBuffer</code> is completely similar to an
				2793	Input one except the callbacks are write() and close().</p>
				2794
				2795	<h3><a name="entities">The entities loader</a></h3>
				2796
				2797	<p>The entity loader resolves requests for new entities and create inputs for
				2798	the parser. Creating an input from a filename or an URI string is done
				2799	through the xmlNewInputFromFile() routine. The default entity loader do not
				2800	handle the PUBLIC identifier associated with an entity (if any). So it just
				2801	calls xmlNewInputFromFile() with the SYSTEM identifier (which is mandatory in
				2802	XML).</p>
				2803
				2804	<p>If you want to hook up a catalog mechanism then you simply need to
				2805	override the default entity loader, here is an example:</p>
				2806	<pre>#include <libxml/xmlIO.h>
				2807
				2808	xmlExternalEntityLoader defaultLoader = NULL;
				2809
				2810	xmlParserInputPtr
				2811	xmlMyExternalEntityLoader(const char URL, const char ID,
				2812	xmlParserCtxtPtr ctxt) {
				2813	xmlParserInputPtr ret;
				2814	const char *fileID = NULL;
				2815	/* lookup for the fileID depending on ID */
				2816
				2817	ret = xmlNewInputFromFile(ctxt, fileID);
				2818	if (ret != NULL)
				2819	return(ret);
				2820	if (defaultLoader != NULL)
				2821	ret = defaultLoader(URL, ID, ctxt);
				2822	return(ret);
				2823	}
				2824
				2825	int main(..) {
				2826	...
				2827
				2828	/*
				2829	* Install our own entity loader
				2830	*/
				2831	defaultLoader = xmlGetExternalEntityLoader();
				2832	xmlSetExternalEntityLoader(xmlMyExternalEntityLoader);
				2833
				2834	...
				2835	}</pre>
				2836
				2837	<h3><a name="Example2">Example of customized I/O</a></h3>
				2838
				2839	<p>This example come from <a href="http://xmlsoft.org/messages/0708.html">a
				2840	real use case</a>, xmlDocDump() closes the FILE * passed by the application
				2841	and this was a problem. The <a
				2842	href="http://xmlsoft.org/messages/0711.html">solution</a> was to redefine a
				2843	new output handler with the closing call deactivated:</p>
				2844	<ol>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2845	<li>First define a new I/O output allocator where the output don't close
				2846	the file:
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2847	<pre>xmlOutputBufferPtr
				2848	xmlOutputBufferCreateOwn(FILE *file, xmlCharEncodingHandlerPtr encoder) {
				2849	xmlOutputBufferPtr ret;
				2850
				2851	if (xmlOutputCallbackInitialized == 0)
				2852	xmlRegisterDefaultOutputCallbacks();
				2853
				2854	if (file == NULL) return(NULL);
				2855	ret = xmlAllocOutputBuffer(encoder);
				2856	if (ret != NULL) {
				2857	ret->context = file;
				2858	ret->writecallback = xmlFileWrite;
				2859	ret->closecallback = NULL; /* No close callback */
				2860	}
				2861	return(ret); <br>
Daniel Veillard	1eb2424	2002-03-18 11:33:03 +0000	[diff] [blame]	2862
Daniel Veillard	34ce8be	2002-03-18 19:37:11 +0000	[diff] [blame]	2863
				2864
Daniel Veillard	1927409	2002-03-25 16:48:03 +0000	[diff] [blame]	2865
Daniel Veillard	b2fb8ed	2002-04-01 09:33:12 +0000	[diff] [blame]	2866
Daniel Veillard	7579482	2002-04-11 16:24:32 +0000	[diff] [blame]	2867
Daniel Veillard	a7084cd	2002-04-15 17:12:47 +0000	[diff] [blame]	2868
Daniel Veillard	0bfbb42	2002-04-26 09:21:45 +0000	[diff] [blame]	2869
Daniel Veillard	93d3a47	2002-04-26 14:04:55 +0000	[diff] [blame]	2870
Daniel Veillard	cf27f7c	2002-04-30 07:12:39 +0000	[diff] [blame]	2871
Daniel Veillard	e6d8e20	2002-05-02 06:11:10 +0000	[diff] [blame]	2872
Daniel Veillard	9b6fd30	2002-05-13 12:06:47 +0000	[diff] [blame]	2873
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	2874
Daniel Veillard	2147367	2002-06-17 07:29:22 +0000	[diff] [blame]	2875
Daniel Veillard	782afda	2002-07-08 15:12:49 +0000	[diff] [blame]	2876
Daniel Veillard	42766c0	2002-08-22 20:52:17 +0000	[diff] [blame]	2877
Daniel Veillard	e166254	2002-08-28 11:50:59 +0000	[diff] [blame]	2878
Daniel Veillard	e16b574	2002-09-26 17:50:03 +0000	[diff] [blame]	2879
Daniel Veillard	321be0c	2002-10-08 21:26:42 +0000	[diff] [blame]	2880
Daniel Veillard	4826743	2002-10-18 11:21:38 +0000	[diff] [blame]	2881
Daniel Veillard	dad3f68	2002-11-17 16:47:27 +0000	[diff] [blame]	2882
Daniel Veillard	c14401e	2002-11-20 14:28:17 +0000	[diff] [blame]	2883
Daniel Veillard	f9c4cad	2002-11-22 15:57:07 +0000	[diff] [blame]	2884
Daniel Veillard	9b4bb4d	2002-12-11 19:28:47 +0000	[diff] [blame]	2885
Daniel Veillard	c1eed32	2002-12-12 11:01:32 +0000	[diff] [blame]	2886
Daniel Veillard	7ef0fcb	2002-12-14 10:38:55 +0000	[diff] [blame]	2887
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	2888
				2889
Daniel Veillard	e2830f1	2003-01-08 17:47:49 +0000	[diff] [blame]	2890
Daniel Veillard	98d071d	2003-01-10 09:22:44 +0000	[diff] [blame]	2891
				2892
Daniel Veillard	831e8fd	2003-01-25 11:45:34 +0000	[diff] [blame]	2893
Daniel Veillard	72fef16	2003-02-05 14:31:19 +0000	[diff] [blame]	2894
Daniel Veillard	1d788d2	2003-02-10 16:21:58 +0000	[diff] [blame]	2895
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	2896
Daniel Veillard	806cada	2003-03-19 21:58:59 +0000	[diff] [blame]	2897
				2898
Daniel Veillard	d8da01c	2003-03-24 15:58:23 +0000	[diff] [blame^]	2899
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2900	} </pre>
				2901	</li>
				2902	<li>And then use it to save the document:
				2903	<pre>FILE *f;
				2904	xmlOutputBufferPtr output;
				2905	xmlDocPtr doc;
				2906	int res;
				2907
				2908	f = ...
				2909	doc = ....
				2910
				2911	output = xmlOutputBufferCreateOwn(f, NULL);
				2912	res = xmlSaveFileTo(output, doc, NULL);
				2913	</pre>
				2914	</li>
				2915	</ol>
				2916
				2917	<h2><a name="Catalog">Catalog support</a></h2>
				2918
				2919	<p>Table of Content:</p>
				2920	<ol>
				2921	<li><a href="General2">General overview</a></li>
				2922	<li><a href="#definition">The definition</a></li>
				2923	<li><a href="#Simple">Using catalogs</a></li>
				2924	<li><a href="#Some">Some examples</a></li>
				2925	<li><a href="#reference">How to tune catalog usage</a></li>
				2926	<li><a href="#validate">How to debug catalog processing</a></li>
				2927	<li><a href="#Declaring">How to create and maintain catalogs</a></li>
				2928	<li><a href="#implemento">The implementor corner quick review of the
				2929	API</a></li>
				2930	<li><a href="#Other">Other resources</a></li>
				2931	</ol>
				2932
				2933	<h3><a name="General2">General overview</a></h3>
				2934
				2935	<p>What is a catalog? Basically it's a lookup mechanism used when an entity
				2936	(a file or a remote resource) references another entity. The catalog lookup
				2937	is inserted between the moment the reference is recognized by the software
				2938	(XML parser, stylesheet processing, or even images referenced for inclusion
				2939	in a rendering) and the time where loading that resource is actually
				2940	started.</p>
				2941
				2942	<p>It is basically used for 3 things:</p>
				2943	<ul>
				2944	<li>mapping from "logical" names, the public identifiers and a more
				2945	concrete name usable for download (and URI). For example it can associate
				2946	the logical name
				2947	<p>"-//OASIS//DTD DocBook XML V4.1.2//EN"</p>
				2948	<p>of the DocBook 4.1.2 XML DTD with the actual URL where it can be
				2949	downloaded</p>
				2950	<p>http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd</p>
				2951	</li>
				2952	<li>remapping from a given URL to another one, like an HTTP indirection
				2953	saying that
				2954	<p>"http://www.oasis-open.org/committes/tr.xsl"</p>
				2955	<p>should really be looked at</p>
				2956	<p>"http://www.oasis-open.org/committes/entity/stylesheets/base/tr.xsl"</p>
				2957	</li>
				2958	<li>providing a local cache mechanism allowing to load the entities
				2959	associated to public identifiers or remote resources, this is a really
				2960	important feature for any significant deployment of XML or SGML since it
				2961	allows to avoid the aleas and delays associated to fetching remote
				2962	resources.</li>
				2963	</ul>
				2964
				2965	<h3><a name="definition">The definitions</a></h3>
				2966
				2967	<p>Libxml, as of 2.4.3 implements 2 kind of catalogs:</p>
				2968	<ul>
				2969	<li>the older SGML catalogs, the official spec is SGML Open Technical
				2970	Resolution TR9401:1997, but is better understood by reading <a
				2971	href="http://www.jclark.com/sp/catalog.htm">the SP Catalog page</a> from
				2972	James Clark. This is relatively old and not the preferred mode of
				2973	operation of libxml.</li>
				2974	<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]	2975	Catalogs</a> is far more flexible, more recent, uses an XML syntax and
				2976	should scale quite better. This is the default option of libxml.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	2977	</ul>
				2978
				2979	<p></p>
				2980
				2981	<h3><a name="Simple">Using catalog</a></h3>
				2982
				2983	<p>In a normal environment libxml will by default check the presence of a
				2984	catalog in /etc/xml/catalog, and assuming it has been correctly populated,
				2985	the processing is completely transparent to the document user. To take a
				2986	concrete example, suppose you are authoring a DocBook document, this one
				2987	starts with the following DOCTYPE definition:</p>
				2988	<pre><?xml version='1.0'?>
				2989	<!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
				2990	"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd"></pre>
				2991
				2992	<p>When validating the document with libxml, the catalog will be
				2993	automatically consulted to lookup the public identifier "-//Norman Walsh//DTD
				2994	DocBk XML V3.1.4//EN" and the system identifier
				2995	"http://nwalsh.com/docbook/xml/3.1.4/db3xml.dtd", and if these entities have
				2996	been installed on your system and the catalogs actually point to them, libxml
				2997	will fetch them from the local disk.</p>
				2998
				2999	<p style="font-size: 10pt"><strong>Note</strong>: Really don't use this
				3000	DOCTYPE example it's a really old version, but is fine as an example.</p>
				3001
				3002	<p>Libxml will check the catalog each time that it is requested to load an
				3003	entity, this includes DTD, external parsed entities, stylesheets, etc ... If
				3004	your system is correctly configured all the authoring phase and processing
				3005	should use only local files, even if your document stays portable because it
				3006	uses the canonical public and system ID, referencing the remote document.</p>
				3007
				3008	<h3><a name="Some">Some examples:</a></h3>
				3009
				3010	<p>Here is a couple of fragments from XML Catalogs used in libxml early
				3011	regression tests in <code>test/catalogs</code> :</p>
				3012	<pre><?xml version="1.0"?>
				3013	<!DOCTYPE catalog PUBLIC
				3014	"-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3015	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3016	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
				3017	<public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
				3018	uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
				3019	...</pre>
				3020
				3021	<p>This is the beginning of a catalog for DocBook 4.1.2, XML Catalogs are
				3022	written in XML, there is a specific namespace for catalog elements
				3023	"urn:oasis:names:tc:entity:xmlns:xml:catalog". The first entry in this
				3024	catalog is a <code>public</code> mapping it allows to associate a Public
				3025	Identifier with an URI.</p>
				3026	<pre>...
				3027	<rewriteSystem systemIdStartString="http://www.oasis-open.org/docbook/"
				3028	rewritePrefix="file:///usr/share/xml/docbook/"/>
				3029	...</pre>
				3030
				3031	<p>A <code>rewriteSystem</code> is a very powerful instruction, it says that
				3032	any URI starting with a given prefix should be looked at another URI
				3033	constructed by replacing the prefix with an new one. In effect this acts like
				3034	a cache system for a full area of the Web. In practice it is extremely useful
				3035	with a file prefix if you have installed a copy of those resources on your
				3036	local system.</p>
				3037	<pre>...
				3038	<delegatePublic publicIdStartString="-//OASIS//DTD XML Catalog //"
				3039	catalog="file:///usr/share/xml/docbook.xml"/>
				3040	<delegatePublic publicIdStartString="-//OASIS//ENTITIES DocBook XML"
				3041	catalog="file:///usr/share/xml/docbook.xml"/>
				3042	<delegatePublic publicIdStartString="-//OASIS//DTD DocBook XML"
				3043	catalog="file:///usr/share/xml/docbook.xml"/>
				3044	<delegateSystem systemIdStartString="http://www.oasis-open.org/docbook/"
				3045	catalog="file:///usr/share/xml/docbook.xml"/>
				3046	<delegateURI uriStartString="http://www.oasis-open.org/docbook/"
				3047	catalog="file:///usr/share/xml/docbook.xml"/>
				3048	...</pre>
				3049
				3050	<p>Delegation is the core features which allows to build a tree of catalogs,
				3051	easier to maintain than a single catalog, based on Public Identifier, System
				3052	Identifier or URI prefixes it instructs the catalog software to look up
				3053	entries in another resource. This feature allow to build hierarchies of
				3054	catalogs, the set of entries presented should be sufficient to redirect the
				3055	resolution of all DocBook references to the specific catalog in
				3056	<code>/usr/share/xml/docbook.xml</code> this one in turn could delegate all
				3057	references for DocBook 4.2.1 to a specific catalog installed at the same time
				3058	as the DocBook resources on the local machine.</p>
				3059
				3060	<h3><a name="reference">How to tune catalog usage:</a></h3>
				3061
				3062	<p>The user can change the default catalog behaviour by redirecting queries
				3063	to its own set of catalogs, this can be done by setting the
				3064	<code>XML_CATALOG_FILES</code> environment variable to a list of catalogs, an
				3065	empty one should deactivate loading the default <code>/etc/xml/catalog</code>
				3066	default catalog</p>
				3067
				3068	<h3><a name="validate">How to debug catalog processing:</a></h3>
				3069
				3070	<p>Setting up the <code>XML_DEBUG_CATALOG</code> environment variable will
				3071	make libxml output debugging informations for each catalog operations, for
				3072	example:</p>
				3073	<pre>orchis:~/XML -> xmllint --memory --noout test/ent2
				3074	warning: failed to load external entity "title.xml"
				3075	orchis:~/XML -> export XML_DEBUG_CATALOG=
				3076	orchis:~/XML -> xmllint --memory --noout test/ent2
				3077	Failed to parse catalog /etc/xml/catalog
				3078	Failed to parse catalog /etc/xml/catalog
				3079	warning: failed to load external entity "title.xml"
				3080	Catalogs cleanup
				3081	orchis:~/XML -> </pre>
				3082
				3083	<p>The test/ent2 references an entity, running the parser from memory makes
				3084	the base URI unavailable and the the "title.xml" entity cannot be loaded.
				3085	Setting up the debug environment variable allows to detect that an attempt is
				3086	made to load the <code>/etc/xml/catalog</code> but since it's not present the
				3087	resolution fails.</p>
				3088
				3089	<p>But the most advanced way to debug XML catalog processing is to use the
				3090	<strong>xmlcatalog</strong> command shipped with libxml2, it allows to load
				3091	catalogs and make resolution queries to see what is going on. This is also
				3092	used for the regression tests:</p>
				3093	<pre>orchis:~/XML -> ./xmlcatalog test/catalogs/docbook.xml \
				3094	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3095	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3096	orchis:~/XML -> </pre>
				3097
				3098	<p>For debugging what is going on, adding one -v flags increase the verbosity
				3099	level to indicate the processing done (adding a second flag also indicate
				3100	what elements are recognized at parsing):</p>
				3101	<pre>orchis:~/XML -> ./xmlcatalog -v test/catalogs/docbook.xml \
				3102	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3103	Parsing catalog test/catalogs/docbook.xml's content
				3104	Found public match -//OASIS//DTD DocBook XML V4.1.2//EN
				3105	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3106	Catalogs cleanup
				3107	orchis:~/XML -> </pre>
				3108
				3109	<p>A shell interface is also available to debug and process multiple queries
				3110	(and for regression tests):</p>
				3111	<pre>orchis:~/XML -> ./xmlcatalog -shell test/catalogs/docbook.xml \
				3112	"-//OASIS//DTD DocBook XML V4.1.2//EN"
				3113	> help
				3114	Commands available:
				3115	public PublicID: make a PUBLIC identifier lookup
				3116	system SystemID: make a SYSTEM identifier lookup
				3117	resolve PublicID SystemID: do a full resolver lookup
				3118	add 'type' 'orig' 'replace' : add an entry
				3119	del 'values' : remove values
				3120	dump: print the current catalog state
				3121	debug: increase the verbosity level
				3122	quiet: decrease the verbosity level
				3123	exit: quit the shell
				3124	> public "-//OASIS//DTD DocBook XML V4.1.2//EN"
				3125	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd
				3126	> quit
				3127	orchis:~/XML -> </pre>
				3128
				3129	<p>This should be sufficient for most debugging purpose, this was actually
				3130	used heavily to debug the XML Catalog implementation itself.</p>
				3131
				3132	<h3><a name="Declaring">How to create and maintain</a> catalogs:</h3>
				3133
				3134	<p>Basically XML Catalogs are XML files, you can either use XML tools to
				3135	manage them or use <strong>xmlcatalog</strong> for this. The basic step is
				3136	to create a catalog the -create option provide this facility:</p>
				3137	<pre>orchis:~/XML -> ./xmlcatalog --create tst.xml
				3138	<?xml version="1.0"?>
				3139	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3140	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3141	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
				3142	orchis:~/XML -> </pre>
				3143
				3144	<p>By default xmlcatalog does not overwrite the original catalog and save the
				3145	result on the standard output, this can be overridden using the -noout
				3146	option. The <code>-add</code> command allows to add entries in the
				3147	catalog:</p>
				3148	<pre>orchis:~/XML -> ./xmlcatalog --noout --create --add "public" \
				3149	"-//OASIS//DTD DocBook XML V4.1.2//EN" \
				3150	http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd tst.xml
				3151	orchis:~/XML -> cat tst.xml
				3152	<?xml version="1.0"?>
				3153	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" \
				3154	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3155	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
				3156	<public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
				3157	uri="http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"/>
				3158	</catalog>
				3159	orchis:~/XML -> </pre>
				3160
				3161	<p>The <code>-add</code> option will always take 3 parameters even if some of
				3162	the XML Catalog constructs (like nextCatalog) will have only a single
				3163	argument, just pass a third empty string, it will be ignored.</p>
				3164
				3165	<p>Similarly the <code>-del</code> option remove matching entries from the
				3166	catalog:</p>
				3167	<pre>orchis:~/XML -> ./xmlcatalog --del \
				3168	"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" tst.xml
				3169	<?xml version="1.0"?>
				3170	<!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN"
				3171	"http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
				3172	<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog"/>
				3173	orchis:~/XML -> </pre>
				3174
				3175	<p>The catalog is now empty. Note that the matching of <code>-del</code> is
				3176	exact and would have worked in a similar fashion with the Public ID
				3177	string.</p>
				3178
				3179	<p>This is rudimentary but should be sufficient to manage a not too complex
				3180	catalog tree of resources.</p>
				3181
				3182	<h3><a name="implemento">The implementor corner quick review of the
				3183	API:</a></h3>
				3184
				3185	<p>First, and like for every other module of libxml, there is an
				3186	automatically generated <a href="html/libxml-catalog.html">API page for
				3187	catalog support</a>.</p>
				3188
				3189	<p>The header for the catalog interfaces should be included as:</p>
				3190	<pre>#include <libxml/catalog.h></pre>
				3191
				3192	<p>The API is voluntarily kept very simple. First it is not obvious that
				3193	applications really need access to it since it is the default behaviour of
				3194	libxml (Note: it is possible to completely override libxml default catalog by
				3195	using <a href="html/libxml-parser.html">xmlSetExternalEntityLoader</a> to
				3196	plug an application specific resolver).</p>
				3197
				3198	<p>Basically libxml support 2 catalog lists:</p>
				3199	<ul>
				3200	<li>the default one, global shared by all the application</li>
				3201	<li>a per-document catalog, this one is built if the document uses the
				3202	<code>oasis-xml-catalog</code> PIs to specify its own catalog list, it is
				3203	associated to the parser context and destroyed when the parsing context
				3204	is destroyed.</li>
				3205	</ul>
				3206
				3207	<p>the document one will be used first if it exists.</p>
				3208
				3209	<h4>Initialization routines:</h4>
				3210
				3211	<p>xmlInitializeCatalog(), xmlLoadCatalog() and xmlLoadCatalogs() should be
				3212	used at startup to initialize the catalog, if the catalog should be
				3213	initialized with specific values xmlLoadCatalog() or xmlLoadCatalogs()
				3214	should be called before xmlInitializeCatalog() which would otherwise do a
				3215	default initialization first.</p>
				3216
				3217	<p>The xmlCatalogAddLocal() call is used by the parser to grow the document
				3218	own catalog list if needed.</p>
				3219
				3220	<h4>Preferences setup:</h4>
				3221
				3222	<p>The XML Catalog spec requires the possibility to select default
				3223	preferences between public and system delegation,
				3224	xmlCatalogSetDefaultPrefer() allows this, xmlCatalogSetDefaults() and
				3225	xmlCatalogGetDefaults() allow to control if XML Catalogs resolution should
				3226	be forbidden, allowed for global catalog, for document catalog or both, the
				3227	default is to allow both.</p>
				3228
				3229	<p>And of course xmlCatalogSetDebug() allows to generate debug messages
				3230	(through the xmlGenericError() mechanism).</p>
				3231
				3232	<h4>Querying routines:</h4>
				3233
				3234	<p>xmlCatalogResolve(), xmlCatalogResolveSystem(), xmlCatalogResolvePublic()
				3235	and xmlCatalogResolveURI() are relatively explicit if you read the XML
				3236	Catalog specification they correspond to section 7 algorithms, they should
				3237	also work if you have loaded an SGML catalog with a simplified semantic.</p>
				3238
				3239	<p>xmlCatalogLocalResolve() and xmlCatalogLocalResolveURI() are the same but
				3240	operate on the document catalog list</p>
				3241
				3242	<h4>Cleanup and Miscellaneous:</h4>
				3243
				3244	<p>xmlCatalogCleanup() free-up the global catalog, xmlCatalogFreeLocal() is
				3245	the per-document equivalent.</p>
				3246
				3247	<p>xmlCatalogAdd() and xmlCatalogRemove() are used to dynamically modify the
				3248	first catalog in the global list, and xmlCatalogDump() allows to dump a
				3249	catalog state, those routines are primarily designed for xmlcatalog, I'm not
				3250	sure that exposing more complex interfaces (like navigation ones) would be
				3251	really useful.</p>
				3252
				3253	<p>The xmlParseCatalogFile() is a function used to load XML Catalog files,
				3254	it's similar as xmlParseFile() except it bypass all catalog lookups, it's
				3255	provided because this functionality may be useful for client tools.</p>
				3256
				3257	<h4>threaded environments:</h4>
				3258
				3259	<p>Since the catalog tree is built progressively, some care has been taken to
				3260	try to avoid troubles in multithreaded environments. The code is now thread
				3261	safe assuming that the libxml library has been compiled with threads
				3262	support.</p>
				3263
				3264	<p></p>
				3265
				3266	<h3><a name="Other">Other resources</a></h3>
				3267
				3268	<p>The XML Catalog specification is relatively recent so there isn't much
				3269	literature to point at:</p>
				3270	<ul>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3271	<li>You can find a good rant from Norm Walsh about <a
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3272	href="http://www.arbortext.com/Think_Tank/XML_Resources/Issue_Three/issue_three.html">the
				3273	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]	3274	I don't agree with everything presented. Norm also wrote a more recent
				3275	article <a
				3276	href="http://wwws.sun.com/software/xml/developers/resolver/article/">XML
				3277	entities and URI resolvers</a> describing them.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3278	<li>An <a href="http://home.ccil.org/~cowan/XML/XCatalog.html">old XML
				3279	catalog proposal</a> from John Cowan</li>
				3280	<li>The <a href="http://www.rddl.org/">Resource Directory Description
				3281	Language</a> (RDDL) another catalog system but more oriented toward
				3282	providing metadata for XML namespaces.</li>
				3283	<li>the page from the OASIS Technical <a
				3284	href="http://www.oasis-open.org/committees/entity/">Committee on Entity
				3285	Resolution</a> who maintains XML Catalog, you will find pointers to the
				3286	specification update, some background and pointers to others tools
				3287	providing XML Catalog support</li>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3288	<li>Here is a <a href="buildDocBookCatalog">shell script</a> to generate
				3289	XML Catalogs for DocBook 4.1.2 . If it can write to the /etc/xml/
				3290	directory, it will set-up /etc/xml/catalog and /etc/xml/docbook based on
				3291	the resources found on the system. Otherwise it will just create
				3292	~/xmlcatalog and ~/dbkxmlcatalog and doing:
Daniel Veillard	c575b99	2002-02-08 13:28:40 +0000	[diff] [blame]	3293	<p><code>export XMLCATALOG=$HOME/xmlcatalog</code></p>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3294	<p>should allow to process DocBook documentations without requiring
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3295	network accesses for the DTD or stylesheets</p>
Daniel Veillard	35e937a	2002-01-19 22:21:54 +0000	[diff] [blame]	3296	</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3297	<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]	3298	small tarball</a> containing XML Catalogs for DocBook 4.1.2 which seems
				3299	to work fine for me too</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3300	<li>The <a href="http://www.xmlsoft.org/xmlcatalog_man.html">xmlcatalog
				3301	manual page</a></li>
				3302	</ul>
				3303
				3304	<p>If you have suggestions for corrections or additions, simply contact
				3305	me:</p>
				3306
				3307	<h2><a name="library">The parser interfaces</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3308
				3309	<p>This section is directly intended to help programmers getting bootstrapped
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3310	using the XML library from the C language. It is not intended to be
				3311	extensive. I hope the automatically generated documents will provide the
				3312	completeness required, but as a separate set of documents. The interfaces of
				3313	the XML library are by principle low level, there is nearly zero abstraction.
				3314	Those interested in a higher level API should <a href="#DOM">look at
				3315	DOM</a>.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	3316
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3317	<p>The <a href="html/libxml-parser.html">parser interfaces for XML</a> are
				3318	separated from the <a href="html/libxml-htmlparser.html">HTML parser
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3319	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]	3320
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3321	<h3><a name="Invoking">Invoking the parser : the pull method</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3322
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3323	<p>Usually, the first thing to do is to read an XML input. The parser accepts
				3324	documents either from in-memory strings or from files. The functions are
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3325	defined in "parser.h":</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3326	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3327	<dt><code>xmlDocPtr xmlParseMemory(char *buffer, int size);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3328	<dd><p>Parse a null-terminated string containing the document.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3329	</dd>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3330	</dl>
				3331	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3332	<dt><code>xmlDocPtr xmlParseFile(const char *filename);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3333	<dd><p>Parse an XML document contained in a (possibly compressed)
				3334	file.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3335	</dd>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3336	</dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3337
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3338	<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]	3339	failure).</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3340
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3341	<h3 id="Invoking1">Invoking the parser: the push method</h3>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3342
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3343	<p>In order for the application to keep the control when the document is
				3344	being fetched (which is common for GUI based programs) libxml provides a push
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3345	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]	3346	<pre>xmlParserCtxtPtr xmlCreatePushParserCtxt(xmlSAXHandlerPtr sax,
				3347	void *user_data,
				3348	const char *chunk,
				3349	int size,
				3350	const char *filename);
				3351	int xmlParseChunk (xmlParserCtxtPtr ctxt,
				3352	const char *chunk,
				3353	int size,
				3354	int terminate);</pre>
				3355
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3356	<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]	3357	<pre> FILE *f;
				3358
				3359	f = fopen(filename, "r");
				3360	if (f != NULL) {
				3361	int res, size = 1024;
				3362	char chars[1024];
				3363	xmlParserCtxtPtr ctxt;
				3364
				3365	res = fread(chars, 1, 4, f);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3366	if (res > 0) {
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3367	ctxt = xmlCreatePushParserCtxt(NULL, NULL,
				3368	chars, res, filename);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3369	while ((res = fread(chars, 1, size, f)) > 0) {
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3370	xmlParseChunk(ctxt, chars, res, 0);
				3371	}
				3372	xmlParseChunk(ctxt, chars, 0, 1);
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3373	doc = ctxt->myDoc;
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3374	xmlFreeParserCtxt(ctxt);
				3375	}
				3376	}</pre>
				3377
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3378	<p>The HTML parser embedded into libxml also has a push interface; the
				3379	functions are just prefixed by "html" rather than "xml".</p>
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3380
				3381	<h3 id="Invoking2">Invoking the parser: the SAX interface</h3>
				3382
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3383	<p>The tree-building interface makes the parser memory-hungry, first loading
				3384	the document in memory and then building the tree itself. Reading a document
				3385	without building the tree is possible using the SAX interfaces (see SAX.h and
				3386	<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]	3387	Henstridge's documentation</a>). Note also that the push interface can be
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3388	limited to SAX: just use the two first arguments of
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3389	<code>xmlCreatePushParserCtxt()</code>.</p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	3390
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3391	<h3><a name="Building">Building a tree from scratch</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3392
				3393	<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]	3394	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]	3395	also described in <libxml/tree.h>.) For example, here is a piece of
				3396	code that produces the XML document used in the previous examples:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3397	<pre> #include <libxml/tree.h>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	3398	xmlDocPtr doc;
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3399	xmlNodePtr tree, subtree;
				3400
				3401	doc = xmlNewDoc("1.0");
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3402	doc->children = xmlNewDocNode(doc, NULL, "EXAMPLE", NULL);
				3403	xmlSetProp(doc->children, "prop1", "gnome is great");
				3404	xmlSetProp(doc->children, "prop2", "& linux too");
				3405	tree = xmlNewChild(doc->children, NULL, "head", NULL);
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3406	subtree = xmlNewChild(tree, NULL, "title", "Welcome to Gnome");
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3407	tree = xmlNewChild(doc->children, NULL, "chapter", NULL);
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3408	subtree = xmlNewChild(tree, NULL, "title", "The Linux adventure");
				3409	subtree = xmlNewChild(tree, NULL, "p", "bla bla bla ...");
				3410	subtree = xmlNewChild(tree, NULL, "image", NULL);
				3411	xmlSetProp(subtree, "href", "linus.gif");</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3412
				3413	<p>Not really rocket science ...</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3414
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3415	<h3><a name="Traversing">Traversing the tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3416
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3417	<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]	3418	code has access to the internal structure of all the elements of the tree.
				3419	The names should be somewhat simple like <strong>parent</strong>,
Daniel Veillard	306be99	2000-07-03 12:38:45 +0000	[diff] [blame]	3420	<strong>children</strong>, <strong>next</strong>, <strong>prev</strong>,
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3421	<strong>properties</strong>, etc... For example, still with the previous
Daniel Veillard	0142b84	2000-01-14 14:45:24 +0000	[diff] [blame]	3422	example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3423	<pre><code>doc->children->children->children</code></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3424
				3425	<p>points to the title element,</p>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3426	<pre>doc->children->children->next->children->children</pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3427
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3428	<p>points to the text node containing the chapter title "The Linux
				3429	adventure".</p>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3430
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	3431	<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]	3432	present before the document root, so <code>doc->children</code> may point
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3433	to an element which is not the document Root Element; a function
Daniel Veillard	5cb5ab8	1999-12-21 15:35:29 +0000	[diff] [blame]	3434	<code>xmlDocGetRootElement()</code> was added for this purpose.</p>
Daniel Veillard	b24054a	1999-12-18 15:32:46 +0000	[diff] [blame]	3435
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3436	<h3><a name="Modifying">Modifying the tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3437
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3438	<p>Functions are provided for reading and writing the document content. Here
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3439	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]	3440	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3441	<dt><code>xmlAttrPtr xmlSetProp(xmlNodePtr node, const xmlChar *name, const
				3442	xmlChar *value);</code></dt>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3443	<dd><p>This sets (or changes) an attribute carried by an ELEMENT node.
				3444	The value can be NULL.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3445	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3446	</dl>
				3447	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3448	<dt><code>const xmlChar *xmlGetProp(xmlNodePtr node, const xmlChar
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3449	*name);</code></dt>
Daniel Veillard	c92c304	2000-09-29 02:42:04 +0000	[diff] [blame]	3450	<dd><p>This function returns a pointer to new copy of the property
				3451	content. Note that the user must deallocate the result.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3452	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3453	</dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3454
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3455	<p>Two functions are provided for reading and writing the text associated
				3456	with elements:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3457	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3458	<dt><code>xmlNodePtr xmlStringGetNodeList(xmlDocPtr doc, const xmlChar
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3459	*value);</code></dt>
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3460	<dd><p>This function takes an "external" string and converts it to one
				3461	text node or possibly to a list of entity and text nodes. All
				3462	non-predefined entity references like &Gnome; will be stored
				3463	internally as entity nodes, hence the result of the function may not be
				3464	a single node.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3465	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3466	</dl>
				3467	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3468	<dt><code>xmlChar *xmlNodeListGetString(xmlDocPtr doc, xmlNodePtr list, int
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3469	inLine);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3470	<dd><p>This function is the inverse of
				3471	<code>xmlStringGetNodeList()</code>. It generates a new string
				3472	containing the content of the text and entity nodes. Note the extra
				3473	argument inLine. If this argument is set to 1, the function will expand
				3474	entity references. For example, instead of returning the &Gnome;
				3475	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]	3476	"GNU Network Object Model Environment").</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3477	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3478	</dl>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3479
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3480	<h3><a name="Saving">Saving a tree</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3481
				3482	<p>Basically 3 options are possible:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3483	<dl>
Daniel Veillard	dd6b367	1999-09-23 22:19:22 +0000	[diff] [blame]	3484	<dt><code>void xmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3485	*size);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3486	<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]	3487	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3488	</dl>
				3489	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3490	<dt><code>extern void xmlDocDump(FILE *f, xmlDocPtr doc);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3491	<dd><p>Dumps a document to an open file descriptor.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3492	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3493	</dl>
				3494	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3495	<dt><code>int xmlSaveFile(const char *filename, xmlDocPtr cur);</code></dt>
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3496	<dd><p>Saves the document to a file. In this case, the compression
				3497	interface is triggered if it has been turned on.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3498	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3499	</dl>
Daniel Veillard	10c6a8f	1998-10-28 01:00:12 +0000	[diff] [blame]	3500
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3501	<h3><a name="Compressio">Compression</a></h3>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3502
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3503	<p>The library transparently handles compression when doing file-based
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3504	accesses. The level of compression on saves can be turned on either globally
				3505	or individually for one file:</p>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3506	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3507	<dt><code>int xmlGetDocCompressMode (xmlDocPtr doc);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3508	<dd><p>Gets the document compression ratio (0-9).</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3509	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3510	</dl>
				3511	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3512	<dt><code>void xmlSetDocCompressMode (xmlDocPtr doc, int mode);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3513	<dd><p>Sets the document compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3514	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3515	</dl>
				3516	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3517	<dt><code>int xmlGetCompressMode(void);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3518	<dd><p>Gets the default compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3519	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3520	</dl>
				3521	<dl>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3522	<dt><code>void xmlSetCompressMode(int mode);</code></dt>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3523	<dd><p>Sets the default compression ratio.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3524	</dd>
Daniel Veillard	25940b7	1998-10-29 05:51:30 +0000	[diff] [blame]	3525	</dl>
				3526
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3527	<h2><a name="Entities">Entities or no entities</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3528
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3529	<p>Entities in principle are similar to simple C macros. An entity defines an
				3530	abbreviation for a given string that you can reuse many times throughout the
				3531	content of your document. Entities are especially useful when a given string
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3532	may occur frequently within a document, or to confine the change needed to a
				3533	document to a restricted area in the internal subset of the document (at the
				3534	beginning). Example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3535	<pre>1 <?xml version="1.0"?>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3536	2 <!DOCTYPE EXAMPLE SYSTEM "example.dtd" [
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3537	3 <!ENTITY xml "Extensible Markup Language">
				3538	4 ]>
				3539	5 <EXAMPLE>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3540	6 &xml;
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3541	7 </EXAMPLE></pre>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3542
				3543	<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]	3544	its name with '&' and following it by ';' without any spaces added. There
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3545	are 5 predefined entities in libxml allowing you to escape characters with
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3546	predefined meaning in some parts of the xml document content:
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3547	<strong>&lt;</strong> for the character '<', <strong>&gt;</strong>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3548	for the character '>', <strong>&apos;</strong> for the character ''',
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3549	<strong>&quot;</strong> for the character '"', and
				3550	<strong>&amp;</strong> for the character '&'.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3551
				3552	<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]	3553	substitute an entity's content so that you can see the replacement text in
				3554	your application. Or you may prefer to keep entity references as such in the
				3555	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]	3556	precious information (if the user went through the pain of explicitly
				3557	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]	3558	substitute them as saving time). The <a
Daniel Veillard	9cb5ff4	2001-01-29 08:22:21 +0000	[diff] [blame]	3559	href="html/libxml-parser.html#XMLSUBSTITUTEENTITIESDEFAULT">xmlSubstituteEntitiesDefault()</a>
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3560	function allows you to check and change the behaviour, which is to not
				3561	substitute entities by default.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3562
				3563	<p>Here is the DOM tree built by libxml for the previous document in the
				3564	default case:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3565	<pre>/gnome/src/gnome-xml -> ./xmllint --debug test/ent1
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3566	DOCUMENT
				3567	version=1.0
				3568	ELEMENT EXAMPLE
				3569	TEXT
				3570	content=
				3571	ENTITY_REF
				3572	INTERNAL_GENERAL_ENTITY xml
				3573	content=Extensible Markup Language
				3574	TEXT
				3575	content=</pre>
				3576
				3577	<p>And here is the result when substituting entities:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3578	<pre>/gnome/src/gnome-xml -> ./tester --debug --noent test/ent1
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3579	DOCUMENT
				3580	version=1.0
				3581	ELEMENT EXAMPLE
				3582	TEXT
				3583	content= Extensible Markup Language</pre>
				3584
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3585	<p>So, entities or no entities? Basically, it depends on your use case. I
				3586	suggest that you keep the non-substituting default behaviour and avoid using
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3587	entities in your XML document or data if you are not willing to handle the
				3588	entity references elements in the DOM tree.</p>
				3589
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3590	<p>Note that at save time libxml enforces the conversion of the predefined
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3591	entities where necessary to prevent well-formedness problems, and will also
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3592	transparently replace those with chars (i.e. it will not generate entity
Daniel Veillard	88f00ae	2000-03-02 00:15:55 +0000	[diff] [blame]	3593	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]	3594	finding them in the input).</p>
				3595
Daniel Veillard	7b9c4b7	2000-08-25 16:26:50 +0000	[diff] [blame]	3596	<p><span style="background-color: #FF0000">WARNING</span>: handling entities
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3597	on top of the libxml SAX interface is difficult!!! If you plan to use
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3598	non-predefined entities in your documents, then the learning curve to handle
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3599	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]	3600	strongly suggest you consider using the DOM interface instead and let libxml
Daniel Veillard	8c6d6af	2000-08-25 17:14:13 +0000	[diff] [blame]	3601	deal with the complexity rather than trying to do it yourself.</p>
Daniel Veillard	7b9c4b7	2000-08-25 16:26:50 +0000	[diff] [blame]	3602
Daniel Veillard	2f4dfc4	1999-09-24 14:03:48 +0000	[diff] [blame]	3603	<h2><a name="Namespaces">Namespaces</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3604
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3605	<p>The libxml library implements <a
				3606	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]	3607	recognizing namespace constructs in the input, and does namespace lookup
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3608	automatically when building the DOM tree. A namespace declaration is
				3609	associated with an in-memory structure and all elements or attributes within
				3610	that namespace point to it. Hence testing the namespace is a simple and fast
				3611	equality operation at the user level.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3612
Daniel Veillard	f13e1ed	2000-03-06 07:41:49 +0000	[diff] [blame]	3613	<p>I suggest that people using libxml use a namespace, and declare it in the
				3614	root element of their document as the default namespace. Then they don't need
				3615	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]	3616	refinement and merging of data from different sources. This doesn't increase
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3617	the size of the XML output significantly, but significantly increases its
				3618	value in the long-term. Example:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3619	<pre><mydoc xmlns="http://mydoc.example.org/schemas/">
				3620	<elem1>...</elem1>
				3621	<elem2>...</elem2>
				3622	</mydoc></pre>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3623
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3624	<p>The namespace value has to be an absolute URL, but the URL doesn't have to
				3625	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]	3626	attributes with that URL. I suggest to use an URL within a domain you
				3627	control, and that the URL should contain some kind of version information if
				3628	possible. For example, <code>"http://www.gnome.org/gnumeric/1.0/"</code> is a
				3629	good namespace scheme.</p>
Daniel Veillard	ec30341	2000-03-24 13:41:54 +0000	[diff] [blame]	3630
				3631	<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]	3632	version-independent prefix is installed on the root element of your document,
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3633	and if the version information don't match something you know, warn the user
				3634	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]	3635	namespace checking on the prefix value. <foo:text> may be exactly the
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3636	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]	3637	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]	3638	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]	3639	<code>ns</code> field pointing to an xmlNs structure detailing the namespace
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3640	prefix and its URI.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3641
				3642	<p>@@Interfaces@@</p>
				3643
				3644	<p>@@Examples@@</p>
				3645
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3646	<p>Usually people object to using namespaces together with validity checking.
				3647	I will try to make sure that using namespaces won't break validity checking,
				3648	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]	3649	suggest adding namespaces to your document. A default namespace scheme
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3650	<code>xmlns="http://...."</code> should not break validity even on less
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3651	flexible parsers. Using namespaces to mix and differentiate content coming
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3652	from multiple DTDs will certainly break current validation schemes. I will
				3653	try to provide ways to do this, but this may not be portable or
				3654	standardized.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3655
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3656	<h2><a name="Upgrading">Upgrading 1.x code</a></h2>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3657
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3658	<p>Incompatible changes:</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3659
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3660	<p>Version 2 of libxml is the first version introducing serious backward
				3661	incompatible changes. The main goals were:</p>
				3662	<ul>
				3663	<li>a general cleanup. A number of mistakes inherited from the very early
				3664	versions couldn't be changed due to compatibility constraints. Example
				3665	the "childs" element in the nodes.</li>
				3666	<li>Uniformization of the various nodes, at least for their header and link
				3667	parts (doc, parent, children, prev, next), the goal is a simpler
				3668	programming model and simplifying the task of the DOM implementors.</li>
				3669	<li>better conformances to the XML specification, for example version 1.x
				3670	had an heuristic to try to detect ignorable white spaces. As a result the
				3671	SAX event generated were ignorableWhitespace() while the spec requires
				3672	character() in that case. This also mean that a number of DOM node
				3673	containing blank text may populate the DOM tree which were not present
				3674	before.</li>
				3675	</ul>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3676
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3677	<h3>How to fix libxml-1.x code:</h3>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3678
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3679	<p>So client code of libxml designed to run with version 1.x may have to be
				3680	changed to compile against version 2.x of libxml. Here is a list of changes
				3681	that I have collected, they may not be sufficient, so in case you find other
				3682	change which are required, <a href="mailto:Daniel.Ïeillardw3.org">drop me a
				3683	mail</a>:</p>
				3684	<ol>
				3685	<li>The package name have changed from libxml to libxml2, the library name
				3686	is now -lxml2 . There is a new xml2-config script which should be used to
				3687	select the right parameters libxml2</li>
				3688	<li>Node <strong>childs</strong> field has been renamed
				3689	<strong>children</strong> so s/childs/children/g should be applied
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3690	(probability of having "childs" anywhere else is close to 0+</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3691	<li>The document don't have anymore a <strong>root</strong> element it has
				3692	been replaced by <strong>children</strong> and usually you will get a
				3693	list of element here. For example a Dtd element for the internal subset
				3694	and it's declaration may be found in that list, as well as processing
				3695	instructions or comments found before or after the document root element.
				3696	Use <strong>xmlDocGetRootElement(doc)</strong> to get the root element of
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3697	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]	3698	PIs or comments before or after the root element
				3699	s/->root/->children/g will probably do it.</li>
				3700	<li>The white space issue, this one is more complex, unless special case of
				3701	validating parsing, the line breaks and spaces usually used for indenting
				3702	and formatting the document content becomes significant. So they are
				3703	reported by SAX and if your using the DOM tree, corresponding nodes are
				3704	generated. Too approach can be taken:
				3705	<ol>
				3706	<li>lazy one, use the compatibility call
				3707	<strong>xmlKeepBlanksDefault(0)</strong> but be aware that you are
				3708	relying on a special (and possibly broken) set of heuristics of
				3709	libxml to detect ignorable blanks. Don't complain if it breaks or
				3710	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]	3711	<li>the Right Way: change you code to accept possibly insignificant
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3712	blanks characters, or have your tree populated with weird blank text
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3713	nodes. You can spot them using the commodity function
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3714	<strong>xmlIsBlankNode(node)</strong> returning 1 for such blank
				3715	nodes.</li>
				3716	</ol>
				3717	<p>Note also that with the new default the output functions don't add any
				3718	extra indentation when saving a tree in order to be able to round trip
				3719	(read and save) without inflating the document with extra formatting
				3720	chars.</p>
				3721	</li>
				3722	<li>The include path has changed to $prefix/libxml/ and the includes
				3723	themselves uses this new prefix in includes instructions... If you are
				3724	using (as expected) the
				3725	<pre>xml2-config --cflags</pre>
				3726	<p>output to generate you compile commands this will probably work out of
				3727	the box</p>
				3728	</li>
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3729	<li>xmlDetectCharEncoding takes an extra argument indicating the length in
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3730	byte of the head of the document available for character detection.</li>
				3731	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3732
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3733	<h3>Ensuring both libxml-1.x and libxml-2.x compatibility</h3>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3734
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3735	<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]	3736	to allow smooth upgrade of existing libxml v1code while retaining
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3737	compatibility. They offers the following:</p>
				3738	<ol>
				3739	<li>similar include naming, one should use
				3740	<strong>#include<libxml/...></strong> in both cases.</li>
				3741	<li>similar identifiers defined via macros for the child and root fields:
				3742	respectively <strong>xmlChildrenNode</strong> and
				3743	<strong>xmlRootNode</strong></li>
				3744	<li>a new macro <strong>LIBXML_TEST_VERSION</strong> which should be
				3745	inserted once in the client code</li>
				3746	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3747
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3748	<p>So the roadmap to upgrade your existing libxml applications is the
				3749	following:</p>
				3750	<ol>
				3751	<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]	3752	<li>find all occurrences where the xmlDoc <strong>root</strong> field is
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3753	used and change it to <strong>xmlRootNode</strong></li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	3754	<li>similarly find all occurrences where the xmlNode
				3755	<strong>childs</strong> field is used and change it to
				3756	<strong>xmlChildrenNode</strong></li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3757	<li>add a <strong>LIBXML_TEST_VERSION</strong> macro somewhere in your
				3758	<strong>main()</strong> or in the library init entry point</li>
				3759	<li>Recompile, check compatibility, it should still work</li>
Daniel Veillard	c0801af	2002-05-28 16:28:42 +0000	[diff] [blame]	3760	<li>Change your configure script to look first for xml2-config and fall
				3761	back using xml-config . Use the --cflags and --libs output of the command
				3762	as the Include and Linking parameters needed to use libxml.</li>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3763	<li>install libxml2-2.3.x and libxml2-devel-2.3.x (libxml-1.8.y and
				3764	libxml-devel-1.8.y can be kept simultaneously)</li>
				3765	<li>remove your config.cache, relaunch your configuration mechanism, and
				3766	recompile, if steps 2 and 3 were done right it should compile as-is</li>
				3767	<li>Test that your application is still running correctly, if not this may
				3768	be due to extra empty nodes due to formating spaces being kept in libxml2
				3769	contrary to libxml1, in that case insert xmlKeepBlanksDefault(1) in your
				3770	code before calling the parser (next to
				3771	<strong>LIBXML_TEST_VERSION</strong> is a fine place).</li>
				3772	</ol>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3773
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3774	<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]	3775
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	3776	<p>Let me put some emphasis on the fact that there is far more changes from
				3777	libxml 1.x to 2.x than the ones you may have to patch for. The overall code
				3778	has been considerably cleaned up and the conformance to the XML specification
				3779	has been drastically improved too. Don't take those changes as an excuse to
				3780	not upgrade, it may cost a lot on the long term ...</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3781
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	3782	<h2><a name="Thread">Thread safety</a></h2>
				3783
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	3784	<p>Starting with 2.4.7, libxml makes provisions to ensure that concurrent
Daniel Veillard	52dcab3	2001-10-30 12:51:17 +0000	[diff] [blame]	3785	threads can safely work in parallel parsing different documents. There is
				3786	however a couple of things to do to ensure it:</p>
				3787	<ul>
				3788	<li>configure the library accordingly using the --with-threads options</li>
				3789	<li>call xmlInitParser() in the "main" thread before using any of the
				3790	libxml API (except possibly selecting a different memory allocator)</li>
				3791	</ul>
				3792
				3793	<p>Note that the thread safety cannot be ensured for multiple threads sharing
				3794	the same document, the locking must be done at the application level, libxml
				3795	exports a basic mutex and reentrant mutexes API in <libxml/threads.h>.
				3796	The parts of the library checked for thread safety are:</p>
				3797	<ul>
				3798	<li>concurrent loading</li>
				3799	<li>file access resolution</li>
				3800	<li>catalog access</li>
				3801	<li>catalog building</li>
				3802	<li>entities lookup/accesses</li>
				3803	<li>validation</li>
				3804	<li>global variables per-thread override</li>
				3805	<li>memory handling</li>
				3806	</ul>
				3807
				3808	<p>XPath is supposed to be thread safe now, but this wasn't tested
				3809	seriously.</p>
				3810
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	3811	<h2><a name="DOM"></a><a name="Principles">DOM Principles</a></h2>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3812
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3813	<p><a href="http://www.w3.org/DOM/">DOM</a> stands for the <em>Document
				3814	Object Model</em>; this is an API for accessing XML or HTML structured
				3815	documents. Native support for DOM in Gnome is on the way (module gnome-dom),
				3816	and will be based on gnome-xml. This will be a far cleaner interface to
				3817	manipulate XML files within Gnome since it won't expose the internal
				3818	structure.</p>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3819
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3820	<p>The current DOM implementation on top of libxml is the <a
Daniel Veillard	a47fb3d	2001-03-25 17:23:49 +0000	[diff] [blame]	3821	href="http://cvs.gnome.org/lxr/source/gdome2/">gdome2 Gnome module</a>, this
				3822	is a full DOM interface, thanks to Paolo Casarini, check the <a
				3823	href="http://www.cs.unibo.it/~casarini/gdome2/">Gdome2 homepage</a> for more
				3824	informations.</p>
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	3825
Daniel Veillard	3500838	1999-10-25 13:15:52 +0000	[diff] [blame]	3826	<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]	3827
				3828	<p>Here is a real size example, where the actual content of the application
				3829	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]	3830	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]	3831	storage structure. Here is an <a href="gjobs.xml">XML encoded jobs
				3832	base</a>:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3833	<pre><?xml version="1.0"?>
				3834	<gjob:Helping xmlns:gjob="http://www.gnome.org/some-location">
				3835	<gjob:Jobs>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3836
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3837	<gjob:Job>
				3838	<gjob:Project ID="3"/>
				3839	<gjob:Application>GBackup</gjob:Application>
				3840	<gjob:Category>Development</gjob:Category>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3841
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3842	<gjob:Update>
				3843	<gjob:Status>Open</gjob:Status>
				3844	<gjob:Modified>Mon, 07 Jun 1999 20:27:45 -0400 MET DST</gjob:Modified>
				3845	<gjob:Salary>USD 0.00</gjob:Salary>
				3846	</gjob:Update>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3847
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3848	<gjob:Developers>
				3849	<gjob:Developer>
				3850	</gjob:Developer>
				3851	</gjob:Developers>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3852
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3853	<gjob:Contact>
				3854	<gjob:Person>Nathan Clemons</gjob:Person>
				3855	<gjob:Email>nathan@windsofstorm.net</gjob:Email>
				3856	<gjob:Company>
				3857	</gjob:Company>
				3858	<gjob:Organisation>
				3859	</gjob:Organisation>
				3860	<gjob:Webpage>
				3861	</gjob:Webpage>
				3862	<gjob:Snailmail>
				3863	</gjob:Snailmail>
				3864	<gjob:Phone>
				3865	</gjob:Phone>
				3866	</gjob:Contact>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3867
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3868	<gjob:Requirements>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3869	The program should be released as free software, under the GPL.
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3870	</gjob:Requirements>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3871
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3872	<gjob:Skills>
				3873	</gjob:Skills>
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:Details>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3876	A GNOME based system that will allow a superuser to configure
				3877	compressed and uncompressed files and/or file systems to be backed
				3878	up with a supported media in the system. This should be able to
				3879	perform via find commands generating a list of files that are passed
				3880	to tar, dd, cpio, cp, gzip, etc., to be directed to the tape machine
				3881	or via operations performed on the filesystem itself. Email
				3882	notification and GUI status display very important.
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3883	</gjob:Details>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3884
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3885	</gjob:Job>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3886
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3887	</gjob:Jobs>
				3888	</gjob:Helping></pre>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3889
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3890	<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]	3891	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]	3892	generate the internal structures is harder, and more error prone.</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3893
				3894	<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]	3895	structure. For example, the ordering of the attributes is not significant,
				3896	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]	3897	depend on the order of the children of a given node, unless it really makes
				3898	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]	3899	<pre>/*
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3900	* A person record
				3901	*/
				3902	typedef struct person {
				3903	char *name;
				3904	char *email;
				3905	char *company;
				3906	char *organisation;
				3907	char *smail;
				3908	char *webPage;
				3909	char *phone;
				3910	} person, *personPtr;
				3911
				3912	/*
				3913	* And the code needed to parse it
				3914	*/
				3915	personPtr parsePerson(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
				3916	personPtr ret = NULL;
				3917
				3918	DEBUG("parsePerson\n");
				3919	/*
				3920	* allocate the struct
				3921	*/
				3922	ret = (personPtr) malloc(sizeof(person));
				3923	if (ret == NULL) {
				3924	fprintf(stderr,"out of memory\n");
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3925	return(NULL);
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3926	}
				3927	memset(ret, 0, sizeof(person));
				3928
				3929	/* We don't care what the top level element name is */
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3930	cur = cur->xmlChildrenNode;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3931	while (cur != NULL) {
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3932	if ((!strcmp(cur->name, "Person")) && (cur->ns == ns))
				3933	ret->name = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				3934	if ((!strcmp(cur->name, "Email")) && (cur->ns == ns))
				3935	ret->email = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				3936	cur = cur->next;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3937	}
				3938
				3939	return(ret);
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3940	}</pre>
				3941
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3942	<p>Here are a couple of things to notice:</p>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3943	<ul>
Daniel Veillard	91e9d58	2001-02-26 07:31:12 +0000	[diff] [blame]	3944	<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]	3945	is by nature subject to repetitive constructs and usually exhibits highly
				3946	structured patterns.</li>
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	3947	<li>The two arguments of type <em>xmlDocPtr</em> and <em>xmlNsPtr</em>,
				3948	i.e. the pointer to the global XML document and the namespace reserved to
				3949	the application. Document wide information are needed for example to
				3950	decode entities and it's a good coding practice to define a namespace for
				3951	your application set of data and test that the element and attributes
				3952	you're analyzing actually pertains to your application space. This is
				3953	done by a simple equality test (cur->ns == ns).</li>
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	3954	<li>To retrieve text and attributes value, you can use the function
				3955	<em>xmlNodeListGetString</em> to gather all the text and entity reference
				3956	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]	3957	</ul>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3958
				3959	<p>Here is another piece of code used to parse another level of the
				3960	structure:</p>
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3961	<pre>#include <libxml/tree.h>
Daniel Veillard	361d845	2000-04-03 19:48:13 +0000	[diff] [blame]	3962	/*
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3963	* a Description for a Job
				3964	*/
				3965	typedef struct job {
				3966	char *projectID;
				3967	char *application;
				3968	char *category;
				3969	personPtr contact;
				3970	int nbDevelopers;
				3971	personPtr developers[100]; /* using dynamic alloc is left as an exercise */
				3972	} job, *jobPtr;
				3973
				3974	/*
				3975	* And the code needed to parse it
				3976	*/
				3977	jobPtr parseJob(xmlDocPtr doc, xmlNsPtr ns, xmlNodePtr cur) {
				3978	jobPtr ret = NULL;
				3979
				3980	DEBUG("parseJob\n");
				3981	/*
				3982	* allocate the struct
				3983	*/
				3984	ret = (jobPtr) malloc(sizeof(job));
				3985	if (ret == NULL) {
				3986	fprintf(stderr,"out of memory\n");
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3987	return(NULL);
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3988	}
				3989	memset(ret, 0, sizeof(job));
				3990
				3991	/* We don't care what the top level element name is */
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3992	cur = cur->xmlChildrenNode;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	3993	while (cur != NULL) {
				3994
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	3995	if ((!strcmp(cur->name, "Project")) && (cur->ns == ns)) {
				3996	ret->projectID = xmlGetProp(cur, "ID");
				3997	if (ret->projectID == NULL) {
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	3998	fprintf(stderr, "Project has no ID\n");
				3999	}
				4000	}
Daniel Veillard	60979bd	2000-07-10 12:17:33 +0000	[diff] [blame]	4001	if ((!strcmp(cur->name, "Application")) && (cur->ns == ns))
				4002	ret->application = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				4003	if ((!strcmp(cur->name, "Category")) && (cur->ns == ns))
				4004	ret->category = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);
				4005	if ((!strcmp(cur->name, "Contact")) && (cur->ns == ns))
				4006	ret->contact = parsePerson(doc, ns, cur);
				4007	cur = cur->next;
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4008	}
				4009
				4010	return(ret);
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4011	}</pre>
Daniel Veillard	14fff06	1999-06-22 21:49:07 +0000	[diff] [blame]	4012
Daniel Veillard	ec70e91	2001-02-26 20:10:45 +0000	[diff] [blame]	4013	<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]	4014	boring. Ultimately, it could be possible to write stubbers taking either C
Daniel Veillard	3d6ae1c	2001-08-15 13:12:39 +0000	[diff] [blame]	4015	data structure definitions, a set of XML examples or an XML DTD and produce
				4016	the code needed to import and export the content between C data and XML
				4017	storage. This is left as an exercise to the reader :-)</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4018
Daniel Veillard	6f0adb5	2000-07-03 11:41:26 +0000	[diff] [blame]	4019	<p>Feel free to use <a href="example/gjobread.c">the code for the full C
				4020	parsing example</a> as a template, it is also available with Makefile in the
				4021	Gnome CVS base under gnome-xml/example</p>
Daniel Veillard	b05deb7	1999-08-10 19:04:08 +0000	[diff] [blame]	4022
Daniel Veillard	c310d56	2000-06-23 18:32:15 +0000	[diff] [blame]	4023	<h2><a name="Contributi">Contributions</a></h2>
				4024	<ul>
Daniel Veillard	b8cfbd1	2001-10-25 10:53:28 +0000	[diff] [blame]	4025	<li>Bjorn Reese, William Brack and Thomas Broyer have provided a number of
				4026	patches, Gary Pennington worked on the validation API, threading support
				4027	and Solaris port.</li>
				4028	<li>John Fleck helps maintaining the documentation and man pages.</li>
Daniel Veillard	7b4b2f9	2003-01-06 13:11:20 +0000	[diff] [blame]	4029	<li><a href="mailto:igor@zlatkovic.com">Igor Zlatkovic</a> is now the
				4030	maintainer of the Windows port, <a
				4031	href="http://www.zlatkovic.com/projects/libxml/index.html">he provides
				4032	binaries</a></li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4033	<li><a href="mailto:Gary.Pennington@sun.com">Gary Pennington</a> provides
				4034	<a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillard	e356c28	2001-03-10 12:32:04 +0000	[diff] [blame]	4035	<li><a
				4036	href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard	63d8314	2002-05-20 06:51:05 +0000	[diff] [blame]	4037	Sergeant</a> developed <a
				4038	href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4039	libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
				4040	application server</a></li>
				4041	<li><a href="mailto:fnatter@gmx.net">Felix Natter</a> and <a
				4042	href="mailto:geertk@ai.rug.nl">Geert Kloosterman</a> provide <a
Daniel Veillard	ca98976	2001-06-23 17:39:29 +0000	[diff] [blame]	4043	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]	4044	documentation</li>
Daniel Veillard	af43f63	2002-03-08 15:05:20 +0000	[diff] [blame]	4045	<li><a href="mailto:sherwin@nlm.nih.gov">Ziying Sherwin</a> provided <a
				4046	href="http://xmlsoft.org/messages/0488.html">man pages</a></li>
Daniel Veillard	5168dbf	2001-07-07 00:18:23 +0000	[diff] [blame]	4047	<li>there is a module for <a
				4048	href="http://acs-misc.sourceforge.net/nsxml.html">libxml/libxslt support
				4049	in OpenNSD/AOLServer</a></li>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	4050	<li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provided the
				4051	first version of libxml/libxslt <a
				4052	href="http://www.rexx.com/~dkuhlman">wrappers for Python</a></li>
Daniel Veillard	1aadc44	2001-11-28 13:10:32 +0000	[diff] [blame]	4053	<li>Petr Kozelka provides <a
				4054	href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
				4055	libxml2</a> with Kylix and Delphi and other Pascal compilers</li>
Daniel Veillard	2d347fa	2002-03-17 10:34:11 +0000	[diff] [blame]	4056	<li><a href="mailto:aleksey@aleksey.com">Aleksey Sanin</a> implemented the
				4057	<a href="http://www.w3.org/Signature/">XML Canonicalization and XML
				4058	Digital Signature</a> <a
				4059	href="http://www.aleksey.com/xmlsec/">implementations for libxml2</a></li>
Daniel Veillard	17bed98	2003-02-24 20:11:43 +0000	[diff] [blame]	4060	<li><a href="mailto:Steve.Ball@zveno.com">Steve Ball</a>, <a
				4061	href="http://www.zveno.com/">Zveno</a> and contributors maintain <a
				4062	href="http://tclxml.sourceforge.net/">tcl bindings for libxml2 and
				4063	libxslt</a>, as well as <a
				4064	href="http://tclxml.sf.net/tkxmllint.html">tkxmllint</a> a GUI for
				4065	xmllint and <a href="http://tclxml.sf.net/tkxsltproc.html">tkxsltproc</a>
				4066	a GUI for xsltproc.</li>
Daniel Veillard	c310d56	2000-06-23 18:32:15 +0000	[diff] [blame]	4067	</ul>
				4068
Daniel Veillard	c8eab3a	1999-09-04 18:27:23 +0000	[diff] [blame]	4069	<p></p>
Daniel Veillard	ccb0963	1998-10-27 06:21:04 +0000	[diff] [blame]	4070	</body>
				4071	</html>