Just finished a new tool, KeywordsTxtGenerator.
This simple tool automatically generates an Arduino project keywords.txt from the corresponding project sources. For this, it uses Doxygen and XSLT (version 1.0).
The main component of the current "project" is the XSLT transformation doxygen2keywords.xsl, which transforms a Doxygen xml file to the keywords.txt file. The enclosed Doxygen minimalist configuration file keywords_txt_generator.doxy can be used. But it can also be generated by most Doxygen configuration, just be sure to define GENERATE_XML = YES therein.
For convenience, a Makefile is also supplied. There are two way to use this:
Either unpack all files in the Arduino project directory, and just type make there.
Unpack anywhere, and type makeArduino-project-dir/keywords.txt, (where Arduino-project-dir denotes the Arduino project).
This project is in the public domain.
Prerequisites: doxygen and an XSLT (1.0) processor, for example xsltproc.