In particular, add documentation configuration system, through the
doc/config.texi file.

Fix trac issue #2374.

The script can and will change.

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Just like doc/eval.texi, this file is meant to be included from
ffmpeg-utils.texi, and not to be used as a standalone documentation.

This allows to clean the doc directory from the parent project dir.
The command:
make -C doc clean

does not work as long as the paths specified in doc/Makefile are relative
to the parent dir.

Also it is consitent with "testclean" and "distclean" targets.

Only enable component manual when the corresponding library providing
the feature is enabled.

Move utilities description to a dedicated manual, consistent with what I
did with the rest of the documentation.

With some re-wording by Alexander Strasser <eclipse7@gmx.net>.

With some fixes and better wording by Alexander Strasser
<eclipse7@gmx.net>.

More consistent with the rest of the build system, and more compact.

The option chapter is based on the avoptions_codec.texi auto-generated
file.

Documentation includes only the externally visible API of the installed
headers.

Based on a patch by Anton Khirnov <anton@khirnov.net>.
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Consistent with --enable-doc, and easier to type.

Allow to select specific documentation components, and reliably check for
component dependencies.

In particular, check for perl presence on the system.

Do not rely on shebang directive in the script, whose exact behavior is
system dependent.

Signed-off-by: Mans Rullgard <mans@mansr.com>

There is no much point into splitting documentation for filters. Also
having a separate document for a library is inconsistent.

The $(dir) function used to construct OBJDIRS includes a trailing slash
in the names returned, which GNU make 3.82 does not match to the
slash-less 'doc' in the documentation dependencies, causing parallel
build to fail.  Adding a slash fixes this and still works with make
3.81.
Signed-off-by: Mans Rullgard <mans@mansr.com>

Now that a documentation generator is built in the doc directory,
this is no longer necessary.  Fixes the Make warning:
Makefile:188: target `doc' given more than once in the same rule.

This fixes doc generation in build tree separate from source.
Signed-off-by: Mans Rullgard <mans@mansr.com>

  When generating the .dep files for .texi sources, verbatim includes
(@verbatiminclude) should also be taken into account.
Signed-off-by: Alexander Strasser <eclipse7@gmx.net>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This reverts commit e5cbf24e.

This commits breaks out of tree builds

  Also create a plain text (.txt) file from fate.texi if the makeinfo
program is available.
Signed-off-by: Alexander Strasser <eclipse7@gmx.net>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

  When generating the .dep files for .texi sources, verbatim includes
(@verbatiminclude) should also be taken into account.
Signed-off-by: Alexander Strasser <eclipse7@gmx.net>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Move the platform-specific information in its own file.