validate_configuration

#!/bin/sh

# validate_configuration — Validate Configuration

# Melusina Actions (https://github.com/melusina-org/setup-macports)
# This file is part of Melusina Actions.
#
# Copyright © 2022–2023 Michaël Le Barbier
# All rights reserved.

# This file must be used under the terms of the MIT License.
# This source file is licensed as described in the file LICENSE, which
# you should have received as part of this distribution. The terms
# are also available at https://opensource.org/licenses/MIT

wlog()
{
    {
	printf '%s: ' "$1"
	shift
	printf "$@"
	printf '\n'
    } 1>&2
}

failwith()
{
    local OPTIND OPTION OPTARG status

    status=1
    OPTIND=1

    while getopts 'x:' OPTION; do
        case ${OPTION} in
            x)	status="${OPTARG}";;
            *)	1>&2 printf 'failwith: %s: Unsupported option.\n' "${OPTION}";;
        esac
    done

    shift $(expr ${OPTIND} - 1)

    case "$1" in
	[0-9][0-9][0-9]|[0-9][0-9]|[0-9])
	    status="$1"
	    shift
	    ;;
	*)
	    :
    esac

    wlog 'Error' "$@"
    exit "${status}"
}

main()
{
    if [ "$#" -ne 1 ]; then
	failwith 'Exactly one argument is required.'
    fi

    if [ "$1" = ':no-value' ]; then
	return 0
    fi

    if [ ! -f "$1" ]; then
	failwith 'The pathname \047%s\047 does not designate a regular file.' "$1"
    fi

    if [ ! -r "$1" ]; then
	failwith 'The pathname \047%s\047 does not designate a readable file.' "$1"
    fi
}

main "$@"

# End of file `validate_configuration'