[v2] doc: support building HTML guides with meson

  From: Bruce Richardson <bruce.richardson@intel.com>

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Luca Boccassi <bluca@debian.org>
---
v2: send on behalf of Bruce on request.
    - tell sphinx to create .doctrees working files in the
      parent of the target directory so that they don't get
      installed
    - change the output directory so that it matches the legacy
      makefiles directory structure (on install)
    - add install_dir to fix ninja install
    - add post-install calls to delete .buildinfo sphinx
      temporary file and to install custom.css as the makefiles
      do
The installed directory has been verified to be bit-by-bit
identical to the legacy makefiles with diffoscope.

 doc/api/meson.build    |  5 ++---
 doc/guides/meson.build | 27 +++++++++++++++++++++++++++
 doc/meson.build        | 11 +++++++++++
 3 files changed, 40 insertions(+), 3 deletions(-)
 create mode 100644 doc/guides/meson.build
  

On Wed, 19 Sep 2018 14:48:27 +0100
Luca Boccassi <bluca@debian.org> wrote:

> From: Bruce Richardson <bruce.richardson@intel.com>
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> Signed-off-by: Luca Boccassi <bluca@debian.org>
> ---
> v2: send on behalf of Bruce on request.
>     - tell sphinx to create .doctrees working files in the
>       parent of the target directory so that they don't get
>       installed
>     - change the output directory so that it matches the legacy
>       makefiles directory structure (on install)
>     - add install_dir to fix ninja install
>     - add post-install calls to delete .buildinfo sphinx
>       temporary file and to install custom.css as the makefiles
>       do
> The installed directory has been verified to be bit-by-bit
> identical to the legacy makefiles with diffoscope.
> 
>  doc/api/meson.build    |  5 ++---
>  doc/guides/meson.build | 27 +++++++++++++++++++++++++++
>  doc/meson.build        | 11 +++++++++++
>  3 files changed, 40 insertions(+), 3 deletions(-)
>  create mode 100644 doc/guides/meson.build
> 
> diff --git a/doc/api/meson.build b/doc/api/meson.build
> index 13fcbb8cd7..30bdc573b5 100644
> --- a/doc/api/meson.build
> +++ b/doc/api/meson.build
> @@ -50,7 +50,6 @@ if doxygen.found()
>  		install_dir: htmldir,
>  		build_by_default: false)
>  
> -	run_target('doc', command: 'true', depends: doxy_build)
> -else
> -	run_target('doc', command: ['echo', 'doxygen', 'not', 'found'])
> +	doc_targets += doxy_build
> +	doc_target_names += 'Doxygen_API'
>  endif
> diff --git a/doc/guides/meson.build b/doc/guides/meson.build
> new file mode 100644
> index 0000000000..24f5316c5c
> --- /dev/null
> +++ b/doc/guides/meson.build
> @@ -0,0 +1,27 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright(c) 2018 Intel Corporation
> +
> +sphinx = find_program('sphinx-build', required: get_option('enable_docs'))
> +
> +if sphinx.found()
> +	htmldir = join_paths('share', 'doc', 'dpdk')
> +	html_guides_build = custom_target('html_guides_build',
> +		input: meson.current_source_dir(),
> +		output: 'guides',
> +		command: [sphinx, '-b', 'html', '@INPUT@', meson.current_build_dir() + '/guides',
> +			'-d', meson.current_build_dir() + '/.doctrees'],

This on RHEL 7.5 doesn't work, since old versions of sphinx (I have
v1.1.3) need all options before the paths. I tried to move
"'-d', meson.current_build_dir() + '/.doctrees'" before "'@INPUT@'" and
it worked.

> +		build_by_default: false,
> +		install: get_option('enable_docs'),
> +		install_dir: htmldir)
> +
> +	doc_targets += html_guides_build
> +	doc_target_names += 'HTML_Guides'
> +
> +	# sphinx leaves a .buildinfo in the target directory, which we don't
> +	# want to install. Note that sh -c has to be used, otherwise the
> +	# env var does not get expanded if calling rm/install directly.
> +	meson.add_install_script('sh', '-c',
> +		'rm -f $MESON_INSTALL_DESTDIR_PREFIX/share/doc/dpdk/guides/.buildinfo')
> +	meson.add_install_script('sh', '-c',
> +		'install -D -m0644 $MESON_SOURCE_ROOT/doc/guides/custom.css $MESON_INSTALL_DESTDIR_PREFIX/share/doc/dpdk/guides/_static/css/')

This on RHEL 7.5 doesn't work. I had to append custom.css to DEST
($MESON_INSTALL_DESTDIR_PREFIX/share/doc/dpdk/guides/_static/css/custom.css)
to make it work.

> +endif
> diff --git a/doc/meson.build b/doc/meson.build
> index afca2e7133..c5410d85d6 100644
> --- a/doc/meson.build
> +++ b/doc/meson.build
> @@ -1,4 +1,15 @@
>  # SPDX-License-Identifier: BSD-3-Clause
>  # Copyright(c) 2018 Luca Boccassi <bluca@debian.org>
>  
> +doc_targets = []
> +doc_target_names = []
>  subdir('api')
> +subdir('guides')
> +
> +if doc_targets.length() == 0
> +	message = 'No docs targets found'
> +else
> +	message = 'Building docs:'
> +endif
> +run_target('doc', command: ['echo', message, doc_target_names],
> +	depends: doc_targets)