+# ===========================================================================
+# http://www.gnu.org/software/autoconf-archive/ax_prog_doxygen.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+# DX_INIT_DOXYGEN(PROJECT-NAME, DOXYFILE-PATH, [OUTPUT-DIR])
+# DX_DOXYGEN_FEATURE(ON|OFF)
+# DX_DOT_FEATURE(ON|OFF)
+# DX_HTML_FEATURE(ON|OFF)
+# DX_CHM_FEATURE(ON|OFF)
+# DX_CHI_FEATURE(ON|OFF)
+# DX_MAN_FEATURE(ON|OFF)
+# DX_RTF_FEATURE(ON|OFF)
+# DX_XML_FEATURE(ON|OFF)
+# DX_PDF_FEATURE(ON|OFF)
+# DX_PS_FEATURE(ON|OFF)
+#
+# DESCRIPTION
+#
+# The DX_*_FEATURE macros control the default setting for the given
+# Doxygen feature. Supported features are 'DOXYGEN' itself, 'DOT' for
+# generating graphics, 'HTML' for plain HTML, 'CHM' for compressed HTML
+# help (for MS users), 'CHI' for generating a seperate .chi file by the
+# .chm file, and 'MAN', 'RTF', 'XML', 'PDF' and 'PS' for the appropriate
+# output formats. The environment variable DOXYGEN_PAPER_SIZE may be
+# specified to override the default 'a4wide' paper size.
+#
+# By default, HTML, PDF and PS documentation is generated as this seems to
+# be the most popular and portable combination. MAN pages created by
+# Doxygen are usually problematic, though by picking an appropriate subset
+# and doing some massaging they might be better than nothing. CHM and RTF
+# are specific for MS (note that you can't generate both HTML and CHM at
+# the same time). The XML is rather useless unless you apply specialized
+# post-processing to it.
+#
+# The macros mainly control the default state of the feature. The use can
+# override the default by specifying --enable or --disable. The macros
+# ensure that contradictory flags are not given (e.g.,
+# --enable-doxygen-html and --enable-doxygen-chm,
+# --enable-doxygen-anything with --disable-doxygen, etc.) Finally, each
+# feature will be automatically disabled (with a warning) if the required
+# programs are missing.
+#
+# Once all the feature defaults have been specified, call DX_INIT_DOXYGEN
+# with the following parameters: a one-word name for the project for use
+# as a filename base etc., an optional configuration file name (the
+# default is 'Doxyfile', the same as Doxygen's default), and an optional
+# output directory name (the default is 'doxygen-doc').
+#
+# Automake Support
+#
+# The following is a template aminclude.am file for use with Automake.
+# Make targets and variables values are controlled by the various
+# DX_COND_* conditionals set by autoconf.
+#
+# The provided targets are:
+#
+# doxygen-doc: Generate all doxygen documentation.
+#
+# doxygen-run: Run doxygen, which will generate some of the
+# documentation (HTML, CHM, CHI, MAN, RTF, XML)
+# but will not do the post processing required
+# for the rest of it (PS, PDF, and some MAN).
+#
+# doxygen-man: Rename some doxygen generated man pages.
+#
+# doxygen-ps: Generate doxygen PostScript documentation.
+#
+# doxygen-pdf: Generate doxygen PDF documentation.
+#
+# Note that by default these are not integrated into the automake targets.
+# If doxygen is used to generate man pages, you can achieve this
+# integration by setting man3_MANS to the list of man pages generated and
+# then adding the dependency:
+#
+# $(man3_MANS): doxygen-doc
+#
+# This will cause make to run doxygen and generate all the documentation.
+#
+# The following variable is intended for use in Makefile.am:
+#
+# DX_CLEANFILES = everything to clean.
+#
+# Then add this variable to MOSTLYCLEANFILES.
+#
+# ----- begin aminclude.am -------------------------------------
+#
+# ## --------------------------------- ##
+# ## Format-independent Doxygen rules. ##
+# ## --------------------------------- ##
+#
+# if DX_COND_doc
+#
+# ## ------------------------------- ##
+# ## Rules specific for HTML output. ##
+# ## ------------------------------- ##
+#
+# if DX_COND_html
+#
+# DX_CLEAN_HTML = @DX_DOCDIR@/html
+#
+# endif DX_COND_html
+#
+# ## ------------------------------ ##
+# ## Rules specific for CHM output. ##
+# ## ------------------------------ ##
+#
+# if DX_COND_chm
+#
+# DX_CLEAN_CHM = @DX_DOCDIR@/chm
+#
+# if DX_COND_chi
+#
+# DX_CLEAN_CHI = @DX_DOCDIR@/@PACKAGE@.chi
+#
+# endif DX_COND_chi
+#
+# endif DX_COND_chm
+#
+# ## ------------------------------ ##
+# ## Rules specific for MAN output. ##
+# ## ------------------------------ ##
+#
+# if DX_COND_man
+#
+# DX_CLEAN_MAN = @DX_DOCDIR@/man
+#
+# endif DX_COND_man
+#
+# ## ------------------------------ ##
+# ## Rules specific for RTF output. ##
+# ## ------------------------------ ##
+#
+# if DX_COND_rtf
+#
+# DX_CLEAN_RTF = @DX_DOCDIR@/rtf
+#
+# endif DX_COND_rtf
+#
+# ## ------------------------------ ##
+# ## Rules specific for XML output. ##
+# ## ------------------------------ ##
+#
+# if DX_COND_xml
+#
+# DX_CLEAN_XML = @DX_DOCDIR@/xml
+#
+# endif DX_COND_xml
+#
+# ## ----------------------------- ##
+# ## Rules specific for PS output. ##
+# ## ----------------------------- ##
+#
+# if DX_COND_ps
+#
+# DX_CLEAN_PS = @DX_DOCDIR@/@PACKAGE@.ps
+#
+# DX_PS_GOAL = doxygen-ps
+#
+# doxygen-ps: @DX_DOCDIR@/@PACKAGE@.ps
+#
+# @DX_DOCDIR@/@PACKAGE@.ps: @DX_DOCDIR@/@PACKAGE@.tag
+# cd @DX_DOCDIR@/latex; \
+# rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+# $(DX_LATEX) refman.tex; \
+# $(MAKEINDEX_PATH) refman.idx; \
+# $(DX_LATEX) refman.tex; \
+# countdown=5; \
+# while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+# refman.log > /dev/null 2>&1 \
+# && test $$countdown -gt 0; do \
+# $(DX_LATEX) refman.tex; \
+# countdown=`expr $$countdown - 1`; \
+# done; \
+# $(DX_DVIPS) -o ../@PACKAGE@.ps refman.dvi
+#
+# endif DX_COND_ps
+#
+# ## ------------------------------ ##
+# ## Rules specific for PDF output. ##
+# ## ------------------------------ ##
+#
+# if DX_COND_pdf
+#
+# DX_CLEAN_PDF = @DX_DOCDIR@/@PACKAGE@.pdf
+#
+# DX_PDF_GOAL = doxygen-pdf
+#
+# doxygen-pdf: @DX_DOCDIR@/@PACKAGE@.pdf
+#
+# @DX_DOCDIR@/@PACKAGE@.pdf: @DX_DOCDIR@/@PACKAGE@.tag
+# cd @DX_DOCDIR@/latex; \
+# rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+# $(DX_PDFLATEX) refman.tex; \
+# $(DX_MAKEINDEX) refman.idx; \
+# $(DX_PDFLATEX) refman.tex; \
+# countdown=5; \
+# while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+# refman.log > /dev/null 2>&1 \
+# && test $$countdown -gt 0; do \
+# $(DX_PDFLATEX) refman.tex; \
+# countdown=`expr $$countdown - 1`; \
+# done; \
+# mv refman.pdf ../@PACKAGE@.pdf
+#
+# endif DX_COND_pdf
+#
+# ## ------------------------------------------------- ##
+# ## Rules specific for LaTeX (shared for PS and PDF). ##
+# ## ------------------------------------------------- ##
+#
+# if DX_COND_latex
+#
+# DX_CLEAN_LATEX = @DX_DOCDIR@/latex
+#
+# endif DX_COND_latex
+#
+# .PHONY: doxygen-run doxygen-doc $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+# .INTERMEDIATE: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+# doxygen-run: @DX_DOCDIR@/@PACKAGE@.tag
+#
+# doxygen-doc: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+# @DX_DOCDIR@/@PACKAGE@.tag: $(DX_CONFIG) $(pkginclude_HEADERS)
+# rm -rf @DX_DOCDIR@
+# $(DX_ENV) $(DX_DOXYGEN) $(srcdir)/$(DX_CONFIG)
+#
+# DX_CLEANFILES = \
+# @DX_DOCDIR@/@PACKAGE@.tag \
+# -r \
+# $(DX_CLEAN_HTML) \
+# $(DX_CLEAN_CHM) \
+# $(DX_CLEAN_CHI) \
+# $(DX_CLEAN_MAN) \
+# $(DX_CLEAN_RTF) \
+# $(DX_CLEAN_XML) \
+# $(DX_CLEAN_PS) \
+# $(DX_CLEAN_PDF) \
+# $(DX_CLEAN_LATEX)
+#
+# endif DX_COND_doc
+#
+# ----- end aminclude.am ---------------------------------------
+#
+# LICENSE
+#
+# Copyright (c) 2009 Oren Ben-Kiki <oren@ben-kiki.org>
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice
+# and this notice are preserved. This file is offered as-is, without any
+# warranty.