#!@PERL@ -w
#
# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
#
# SPDX-License-Identifier: MPL-2.0
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, you can obtain one at https://mozilla.org/MPL/2.0/.
#
# See the COPYRIGHT file distributed with this work for additional
# information regarding copyright ownership.

# Input filter for feeding our source code into Doxygen.

# Slurp whole file at once
undef $/;
$_ = <>;

# It turns out that there are a lot of cases where we'd really like to
# use what Doxygen calls "brief" documentation in a comment.  Doxygen
# has a shorthand way of doing this -- if one is writing C++.  ISC
# coding conventions require C, not C++, so we have to do it the
# verbose way, which makes a lot of comments too long to fit on a
# single line without violating another ISC coding standard (80
# character line limit).
#
# So we use Doxygen's input filter mechanism to define our own
# brief comment convention:
#
#	/*% foo */
#
# expands to
#
#	/*! \brief foo */
#
# and
#
#	/*%< foo */
#
# expands to
#
#	/*!< \brief foo */
#
s{/\*%(<?)}{/*!$1 \\brief }g;

# Doxygen appears to strip trailing newlines when reading files
# directly but not when reading from an input filter.  Go figure.
# Future versions of Doxygen might change this, be warned.
#
s{\n+\z}{};

# Done, send the result to Doxygen.
#
print;