Blame - doc/xml.html - platform/external/libxml2

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