source: general/genlib/libxml2.xml@ 2ecff2c5

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;

  <!-- Also update the download, md5, size entities in libxml2py2.xml -->
  <!ENTITY libxml2-download-http "https://download.gnome.org/sources/libxml2/2.13/libxml2-&libxml2-version;.tar.xz">
<!--  <!ENTITY libxml2-download-http "http://xmlsoft.org/sources/libxml2-&libxml2-version;.tar.xz">-->
  <!ENTITY libxml2-download-ftp  " ">
  <!ENTITY libxml2-md5sum        "22a4b108240c3f2aeb1354346055b436">
  <!ENTITY libxml2-size          "2.5 MB">
  <!ENTITY libxml2-buildsize     "110 MB (with tests)">
  <!ENTITY libxml2-time          "0.3 SBU (Using parallelism=4; with tests)">
  <!ENTITY testsuite-version     "20130923">
]>

<sect1 id="libxml2" xreflabel="libxml2-&libxml2-version;">
  <?dbhtml filename="libxml2.html"?>


  <title>libxml2-&libxml2-version;</title>

  <indexterm zone="libxml2">
    <primary sortas="a-libxml2">libxml2</primary>
  </indexterm>

  <sect2 role="package">
    <title>Introduction to libxml2</title>

    <para>
      The <application>libxml2</application> package contains libraries
      and utilities used for parsing XML files.
    </para>

    &lfs121_checked;

    <bridgehead renderas="sect3">Package Information</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Download (HTTP): <ulink url="&libxml2-download-http;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download (FTP): <ulink url="&libxml2-download-ftp;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download MD5 sum: &libxml2-md5sum;
        </para>
      </listitem>
      <listitem>
        <para>
          Download size: &libxml2-size;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated disk space required: &libxml2-buildsize;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated build time: &libxml2-time;
        </para>
      </listitem>
    </itemizedlist>

    <bridgehead renderas="sect3">Additional Downloads</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Required patch:
          <ulink url="&patch-root;/libxml2-&libxml2-version;-upstream_fixes-2.patch"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Optional Test Suite:
          <ulink url="https://www.w3.org/XML/Test/xmlts&testsuite-version;.tar.gz"/> - This
          enables <command>make check</command> to do complete testing.
        </para>
      </listitem>
    </itemizedlist>

    <bridgehead renderas="sect3">libxml2 Dependencies</bridgehead>

    <bridgehead renderas="sect4">Recommended</bridgehead>
    <para role="recommended">
      <xref linkend="icu"/>
    </para>

    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <xref linkend="valgrind"/> (may be used in the tests)
    </para>
  </sect2>

  <sect2 role="installation">
    <title>Installation of libxml2</title>

    <para>
      At first, fix several issues identified and fixed by upstream after
      libxml2-2.13.0 was released:
    </para>

    <screen><userinput>patch -Np1 -i ../libxml2-&libxml2-version;-upstream_fixes-2.patch</userinput></screen>

    <para>
      Install <application>libxml2</application> by running the following
      commands:
    </para>

<screen><userinput>./configure --prefix=/usr           \
            --sysconfdir=/etc       \
            --disable-static        \
            --with-history          \
            --with-icu              \
            PYTHON=/usr/bin/python3 \
            --docdir=/usr/share/doc/libxml2-&libxml2-version; &amp;&amp;
make</userinput></screen>

    <para>
      If you downloaded the test suite, issue the following command:
    </para>

<screen><userinput>tar xf ../xmlts&testsuite-version;.tar.gz</userinput></screen>

    <para>
      To test the results, issue: <command>make check &gt; check.log</command>.
      This command will print several lines of error messages like
      <quote><computeroutput>Failed to parse
      xstc/...</computeroutput></quote> because some test files are missing
      and these messages can be safely ignored.
      A summary of the results can be obtained with <command>grep -E
      '^Total|expected|Ran' check.log</command>. If <xref linkend="valgrind"/> is
      installed and you want to check for memory leaks, replace
      <command>check</command> with <command>check-valgrind</command>.
    </para>

    <note>
      <para>
        The tests use <ulink url="http://localhost/">http://localhost/</ulink>
        to test parsing of external entities. If the machine where you run the
        tests serves as a web site, the tests may hang, depending on the
        content of the file served. It is therefore recommended to shut down
        the server during the tests, as the <systemitem
        class="username">root</systemitem> user:
      </para>

<screen role="nodump" revision="sysv"><userinput>/etc/init.d/httpd stop</userinput></screen>
<screen role="nodump" revision="systemd"><userinput>systemctl stop httpd.service</userinput></screen>

    </note>

    <para>
      Now, as the <systemitem class="username">root</systemitem> user:
    </para>

<screen role="root"><userinput>make install</userinput></screen>

    <para>
      Finally, prevent some packages from unnecessarily linking to ICU using
      the following commands as the &root; user:
    </para>

<screen role="root"><userinput>rm -vf /usr/lib/libxml2.la &amp;&amp;
sed '/libs=/s/xml2.*/xml2"/' -i /usr/bin/xml2-config</userinput></screen>

  </sect2>

  <sect2 role="commands">
    <title>Command Explanations</title>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="../../xincludes/static-libraries.xml"/>

    <para>
      <parameter>--with-history</parameter>: This switch enables
      <application>Readline</application> support when running
      <command>xmlcatalog</command> or <command>xmllint</command> in shell mode.
    </para>

    <para>
      <parameter>--with-icu</parameter>: This switch enables support for
      <application>ICU</application>, which provides additional Unicode support.
      This is needed for some packages in BLFS, such as for QtWebEngine.
    </para>

    <para>
      <parameter>PYTHON=/usr/bin/python3</parameter>: Allows building
      the libxml2 module with Python3 instead of Python2.
    </para>

<!--
    <para>
      <option>- -with-icu</option>: Add this switch if you have built
      <xref linkend="icu"/>, for better unicode support.
    </para>

    <note>
      <para>
        If the <option>- -with-icu</option> switch is used, the BLFS editors
        recommend removing unneeded references to the ICU libraries. This
        will prevent many packages that use libxml2 from unnecessarily linking
        to the ICU libraries.  This, in turn, will prevent the need for
        rebuilding many packages when upgrading ICU to a new major version.
        After installing libxml2, as the &root; user, issue:
      </para>

<screen role="nodump"><userinput>rm -vf /usr/lib/libxml2.la &amp;&amp;
sed '/libs=/s/xml2.*/xml2"/' -i /usr/bin/xml2-config</userinput></screen>
    </note>
-->

  </sect2>

  <sect2 role="content">
    <title>Contents</title>

    <segmentedlist>
      <segtitle>Installed Programs</segtitle>
      <segtitle>Installed Libraries</segtitle>
      <segtitle>Installed Directories</segtitle>

      <seglistitem>
        <seg>
          xml2-config,
          xmlcatalog, and
          xmllint
        </seg>
        <seg>
          libxml2.so
        </seg>
        <seg>
          /usr/include/libxml2,
          /usr/lib/cmake/libxml2,
          /usr/share/doc/libxml2-&libxml2-version;, and
          /usr/share/gtk-doc/html/libxml2
        </seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="xml2-config">
        <term><command>xml2-config</command></term>
        <listitem>
          <para>
            determines the compile and linker flags that should be used to
            compile and link programs that use
            <filename class="libraryfile">libxml2</filename>
          </para>
          <indexterm zone="libxml2 xml2-config">
            <primary sortas="b-xml2-config">xml2-config</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="xmlcatalog">
        <term><command>xmlcatalog</command></term>
        <listitem>
          <para>
            is used to monitor and manipulate XML and SGML catalogs
          </para>
          <indexterm zone="libxml2 xmlcatalog">
            <primary sortas="b-xmlcatalog">xmlcatalog</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="xmllint">
        <term><command>xmllint</command></term>
        <listitem>
          <para>
            parses XML files and outputs reports (based upon options) to detect
            errors in XML coding
          </para>
          <indexterm zone="libxml2 xmllint">
            <primary sortas="b-xmllint">xmllint</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="libxml2-lib">
        <term><filename class="libraryfile">libxml2.so</filename></term>
        <listitem>
          <para>
            provides functions for programs to parse files that use the XML
            format
          </para>
          <indexterm zone="libxml2 libxml2-lib">
            <primary sortas="c-libxml2">libxml2.so</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>