#!/bin/sh

# config.sub: a neutral implementation for modern (cross-)systems.

# any-target: all are assumed to be supported, no door-keeper failures.

# this file is covered by COPYING.BAUTOMAKE.

set -eu

mb_script="$0"

mb_status=1

mb_dstamp='2020-01-18'

mb_target="${1:-}"

mb_extarg="${2:-}"

export LC_ALL=C

config_usage()

{

	printf 'usage:\n'                                   >&2

	printf '\t%s [OPTION]\n' "$mb_script"               >&2

	printf '\t%s (cross-)target-alias\n\n' "$mb_script" >&2

	printf 'Options:\n' >&2

	printf '\t%s\n'            \

		'-h, --help'       \

		'-t, --time-stamp' \

		'-v, --version'    \

		>&2

	printf '\nThis is a neutral config.sub implementation for modern (cross-)systems.' >&2

	printf '\nAll (cross-)targets are assumed to be supported, and there are no door-keeper failures.\n\n' >&2

	printf 'pkgsite: https://git.foss21.org/bautomake\n' >&2

	printf 'pkgbugs: bugs.automake@foss21.org\n'         >&2

	exit ${mb_status}

}

for arg ; do

	case "$arg" in

		-h | --help)

			mb_status=0

			config_usage

			;;

		-t | --time-stamp)

			printf '%s\n' "$mb_dstamp"

			exit 0

			;;

		-v | --version)

			printf 'foss21.org config.sub (%s)\n' "$mb_dstamp"

			exit 0

			;;

		-*)

			printf '%s: the argument `%s is not supported.\n\n' "$mb_script" "$arg'" >&2

			exit 2

	esac

done

# required target argument

if [ -z "$mb_target" ]; then

	config_usage

fi

# no unused arguments

if [ -n "$mb_extarg" ]; then

	mb_status=2

	config_usage

fi

# validation

if [ "$mb_target" != ${mb_target%% *} ]; then

	printf '%s: input error: target alias may not contain spaces.\n\n' "$mb_script" >&2

	exit 2

fi

# compatible output

printf '%s\n' "$mb_target"

# all done

exit 0