This package provides a common set of SGML entities and XML/CSS style sheets used in building/formatting the documentation provided in other X.Org packages. It's typically only needed by people building from source who want to produce formatted documentation from their builds, or those who have installed the HTML version of the documentation, which refers to the included common xorg.css stylesheet. Documents external references ----------------------------- A new feature with version 1.7 is references to documents in other packages. For example a protocol specifications may refer to another one or to a library implementing it. This feature works with PDF, HTML, PS (and epub?) generated documents and will generate links to the other versions of the same type, i.e. html docs will link to other html docs, and pdf docs will link to other pdf docs. Due to the modular nature of the X window System and the flexibility it provides to O/S builders, one should not expect all links to be resolved all the time. A more recent version of a package may be installed or an older version may be retained for a long period of time. Not all packages are installed either. Build challenges ---------------- The X Window System is composed of over 200 packages. The documentation is included with the package it documents so the information matches the code. The build is organized to satisfy C code building requirements, but this paradigm does not fit very well for building documentation. For a document to build a reference to another document, it needs to have information about this document which may or may not be there, or may be at an unexpected version. The document it refers to may also wish to refer to the former document. Local X builds -------------- When building X as a sandbox on a workstation, using a simple build script to configure and build all packages in the right order is all you need to get a working system, including documentation. You will not get all the links in the documentation resolved correctly due to build order and/or bi-directional references. Unless you are updating or testing the documentation, you do not need to worry about this glitch. A simple workaround is to build each affected package using "make clean install && make clean install" in any order. This will give a chance to each package to get information about the other one through the installed files. O/S X builds ------------ O/S builders often repackage X code and documentation, however they face the same challenges as described above. Users can update packages through the package management system or install additional packages. To use the earlier example, if a protocol is installed without its implementing library there will be a broken reference. Build assumptions ----------------- Packages provide great flexibility, including the one to install each package documentation in a separate, totally unrelated directory using the --docdir configure option. For external references to work, it is assumed that the each package installs the documentation using the relative doc/${PACKAGE_TARNAME} location. It is also a requirement that all packages containing DocBook/XML documentation be installed under the same read-only architecture independent installation directory as evidenced by the DATAROOTDIR package value. This value should also be the same for the xorg-sgml-doctools package. The purpose of this requirement is to form a document tree of a known structure such that stylesheets, masterdb, target dbs and other files can be reached. The Docbook stylesheet technology will create references with paths relative to this location. It will navigate up to "doc" using ../ and then navigate down to the document it refers to. Diagnosing a broken reference ----------------------------- A document reference is created at build time while the document is being transformed from Docbook/XML to HTML or another format. If this reference is missing, the document must be rebuilt. To build the reference, the docbook stylesheet consults a database stored in this package which is called masterdb.xml. This database supplies the relative directory structure of where the documents are located as well as including target document references in the various *.db files. These files are generated and installed while the documents are being build. This is what a Docbook/XML reference from docA to docB looks like (docA.xml): Title This is what an HTML reference from docA to docB looks like (docA.html): Title This is what an HTML targetdoc for docB looks like (docB.html.db):
This is what an HTML reference from docA to docB looks like (docA.html) when the reference cannot be resolved: Title This can be caused by one or more of the following: - docB may not longer contain the text (targetptr) docA is referring to. - docB.html.db file may not have been installed by docB package - masterdb.html.xml is missing a entry for docB - masterdb.html.xml cannot be loaded so all refs are broken. - an XSLT processor which does not support xinclude is being used - docB.html.db was generated without --xinclude option for the processor - xsltproc is not at version 1.1.26 or later - for PDF/PS formats, the fragment is ignored, always points to top of docB Some pitfalls ------------------------- in docA.xml: the id must match the file basename. In xorg-*.xsl, supplies docid for *.db. The document id must be unique across all documents. The baseuri attribute in masterdb.xml is required for pdf/ps references to work. It cannot be replaced with olink.base.uri in the makefile. The pdf/ps "inside the document" references only started working with docbook-xsl v 1.76.1 which is not yet available to your favorite O/S. In xorg-fo.xsl, insert.olink.pdf.frag must be set to zero which allows the reference to at least point to the top of the document. XSL toolchain ------------- The following minimum versions are needed for external references to work: XSLT processor: 1.1.26 libxml2: 2.7.6 libxslt1.1: 1.1.26 The exact triplet may vary by distribution, sometimes a version is skipped. If you are close enough, try it. References ---------- http://docbook.org/tdg/en/html/docbook.html http://docbook.sourceforge.net/release/xsl/current/doc/html/ http://docbook.sourceforge.net/release/xsl/current/doc/fo/ http://www.sagehill.net/docbookxsl/OlinkPrintOutput.html ------------------------------------------------------------------------------- All questions regarding this software should be directed at the Xorg mailing list: http://lists.freedesktop.org/mailman/listinfo/xorg Please submit bug reports to the Xorg bugzilla: https://bugs.freedesktop.org/enter_bug.cgi?product=xorg The master development code repository can be found at: git://anongit.freedesktop.org/git/xorg/doc/xorg-sgml-doctools http://cgit.freedesktop.org/xorg/doc/xorg-sgml-doctools For patch submission instructions, see: http://www.x.org/wiki/Development/Documentation/SubmittingPatches For more information on the git code manager, see: http://wiki.x.org/wiki/GitPage