#!/bin/sh
set -eu

cflags() {
	echo "CFLAGS += $*"
}
defstr() {
	cflags "-D'$1=\"$2\"'"
}
defvar() {
	defstr "$1" "$(pkg-config --variable=$3 $2)${4:-}"
}
ldadd() {
	lib=$1; shift
	echo "LDADD.${lib} = $*"
}
config() {
	pkg-config --print-errors "$@"
	cflags $(pkg-config --cflags "$@")
	for lib; do ldadd $lib $(pkg-config --libs $lib); done
}

exec >config.mk

for opt; do
	case "${opt}" in
		(--prefix=*) echo "PREFIX = ${opt#*=}" ;;
		(--bindir=*) echo "BINDIR = ${opt#*=}" ;;
		(--mandir=*) echo "MANDIR = ${opt#*=}" ;;
		(*) echo "warning: unsupported option ${opt}" >&2 ;;
	esac
done

case "$(uname)" in
	(OpenBSD)
		;;
	(Linux)
		cflags -D_GNU_SOURCE
		config libtls
		;;
	(*)
		config libtls
		;;
esac