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Diffstat (limited to 'Documentation/doc-guide/sphinx.rst')
| -rw-r--r-- | Documentation/doc-guide/sphinx.rst | 113 |
1 files changed, 87 insertions, 26 deletions
diff --git a/Documentation/doc-guide/sphinx.rst b/Documentation/doc-guide/sphinx.rst index 1228b85f6f77..8081ebfe48bc 100644 --- a/Documentation/doc-guide/sphinx.rst +++ b/Documentation/doc-guide/sphinx.rst @@ -28,7 +28,7 @@ Sphinx Install ============== The ReST markups currently used by the Documentation/ files are meant to be -built with ``Sphinx`` version 1.7 or higher. +built with ``Sphinx`` version 2.4.4 or higher. There's a script that checks for the Sphinx requirements. Please see :ref:`sphinx-pre-install` for further details. @@ -48,17 +48,14 @@ or ``virtualenv``, depending on how your distribution packaged Python 3. on the Sphinx version, it should be installed separately, with ``pip install sphinx_rtd_theme``. - #) Some ReST pages contain math expressions. Due to the way Sphinx works, - those expressions are written using LaTeX notation. It needs texlive - installed with amsfonts and amsmath in order to evaluate them. +In summary, if you want to install the latest version of Sphinx, you +should do:: -In summary, if you want to install Sphinx version 2.4.4, you should do:: + $ virtualenv sphinx_latest + $ . sphinx_latest/bin/activate + (sphinx_latest) $ pip install -r Documentation/sphinx/requirements.txt - $ virtualenv sphinx_2.4.4 - $ . sphinx_2.4.4/bin/activate - (sphinx_2.4.4) $ pip install -r Documentation/sphinx/requirements.txt - -After running ``. sphinx_2.4.4/bin/activate``, the prompt will change, +After running ``. sphinx_latest/bin/activate``, the prompt will change, in order to indicate that you're using the new environment. If you open a new shell, you need to rerun this command to enter again at the virtual environment before building the documentation. @@ -67,8 +64,7 @@ Image output ------------ The kernel documentation build system contains an extension that -handles images on both GraphViz and SVG formats (see -:ref:`sphinx_kfigure`). +handles images in both GraphViz and SVG formats (see :ref:`sphinx_kfigure`). For it to work, you need to install both GraphViz and ImageMagick packages. If those packages are not installed, the build system will @@ -86,12 +82,33 @@ Depending on the distribution, you may also need to install a series of ``texlive`` packages that provide the minimal set of functionalities required for ``XeLaTeX`` to work. +Math Expressions in HTML +------------------------ + +Some ReST pages contain math expressions. Due to the way Sphinx works, +those expressions are written using LaTeX notation. +There are two options for Sphinx to render math expressions in html output. +One is an extension called `imgmath`_ which converts math expressions into +images and embeds them in html pages. +The other is an extension called `mathjax`_ which delegates math rendering +to JavaScript capable web browsers. +The former was the only option for pre-6.1 kernel documentation and it +requires quite a few texlive packages including amsfonts and amsmath among +others. + +Since kernel release 6.1, html pages with math expressions can be built +without installing any texlive packages. See `Choice of Math Renderer`_ for +further info. + +.. _imgmath: https://www.sphinx-doc.org/en/master/usage/extensions/math.html#module-sphinx.ext.imgmath +.. _mathjax: https://www.sphinx-doc.org/en/master/usage/extensions/math.html#module-sphinx.ext.mathjax + .. _sphinx-pre-install: Checking for Sphinx dependencies -------------------------------- -There's a script that automatically check for Sphinx dependencies. If it can +There's a script that automatically checks for Sphinx dependencies. If it can recognize your distribution, it will also give a hint about the install command line options for your distro:: @@ -130,11 +147,9 @@ section of ``make help``. The generated documentation is placed in format-specific subdirectories under ``Documentation/output``. To generate documentation, Sphinx (``sphinx-build``) must obviously be -installed. For prettier HTML output, the Read the Docs Sphinx theme -(``sphinx_rtd_theme``) is used if available. For PDF output you'll also need -``XeLaTeX`` and ``convert(1)`` from ImageMagick -(https://www.imagemagick.org).\ [#ink]_ -All of these are widely available and packaged in distributions. +installed. For PDF output you'll also need ``XeLaTeX`` and ``convert(1)`` +from ImageMagick (https://www.imagemagick.org).\ [#ink]_ All of these are +widely available and packaged in distributions. To pass extra options to Sphinx, you can use the ``SPHINXOPTS`` make variable. For example, use ``make SPHINXOPTS=-v htmldocs`` to get more verbose @@ -143,12 +158,8 @@ output. It is also possible to pass an extra DOCS_CSS overlay file, in order to customize the html layout, by using the ``DOCS_CSS`` make variable. -By default, the build will try to use the Read the Docs sphinx theme: - - https://github.com/readthedocs/sphinx_rtd_theme - -If the theme is not available, it will fall-back to the classic one. - +By default, the "Alabaster" theme is used to build the HTML documentation; +this theme is bundled with Sphinx and need not be installed separately. The Sphinx theme can be overridden by using the ``DOCS_THEME`` make variable. There is another make variable ``SPHINXDIRS``, which is useful when test @@ -164,6 +175,38 @@ To remove the generated documentation, run ``make cleandocs``. as well would improve the quality of images embedded in PDF documents, especially for kernel releases 5.18 and later. +Choice of Math Renderer +----------------------- + +Since kernel release 6.1, mathjax works as a fallback math renderer for +html output.\ [#sph1_8]_ + +Math renderer is chosen depending on available commands as shown below: + +.. table:: Math Renderer Choices for HTML + + ============= ================= ============ + Math renderer Required commands Image format + ============= ================= ============ + imgmath latex, dvipng PNG (raster) + mathjax + ============= ================= ============ + +The choice can be overridden by setting an environment variable +``SPHINX_IMGMATH`` as shown below: + +.. table:: Effect of Setting ``SPHINX_IMGMATH`` + + ====================== ======== + Setting Renderer + ====================== ======== + ``SPHINX_IMGMATH=yes`` imgmath + ``SPHINX_IMGMATH=no`` mathjax + ====================== ======== + +.. [#sph1_8] Fallback of math renderer requires Sphinx >=1.8. + + Writing Documentation ===================== @@ -240,7 +283,7 @@ Here are some specific guidelines for the kernel documentation: from highlighting. For a short snippet of code embedded in the text, use \`\`. -the C domain +The C domain ------------ The **Sphinx C Domain** (name c) is suited for documentation of C API. E.g. a @@ -270,9 +313,18 @@ the documentation build system will automatically turn a reference to function name exists. If you see ``c:func:`` use in a kernel document, please feel free to remove it. +Tables +------ + +ReStructuredText provides several options for table syntax. Kernel style for +tables is to prefer *simple table* syntax or *grid table* syntax. See the +`reStructuredText user reference for table syntax`_ for more details. + +.. _reStructuredText user reference for table syntax: + https://docutils.sourceforge.io/docs/user/rst/quickref.html#tables list tables ------------ +~~~~~~~~~~~ The list-table formats can be useful for tables that are not easily laid out in the usual Sphinx ASCII-art formats. These formats are nearly @@ -383,6 +435,15 @@ path. For information on cross-referencing to kernel-doc functions or types, see Documentation/doc-guide/kernel-doc.rst. +Referencing commits +~~~~~~~~~~~~~~~~~~~ + +References to git commits are automatically hyperlinked given that they are +written in one of these formats:: + + commit 72bf4f1767f0 + commit 72bf4f1767f0 ("net: do not leave an empty skb in write queue") + .. _sphinx_kfigure: Figures & Images |