#!/bin/sh

# Returns the absolute path of a given string
abspath () { case "$1" in /*)printf "%s\n" "$1";; *)printf "%s\n" "$PWD/$1";; esac; }

# Compares versions of software of the format X.Y.Z
do_version_check() {
    [ "$1" = "$2" ] && return 10

    ver1front=$(printf "%s" "$1" | cut -d "." -f -1)
    ver1back=$(printf "%s" "$1" | cut -d "." -f 2-)
    ver2front=$(printf "%s" "$2" | cut -d "." -f -1)
    ver2back=$(printf "%s" "$2" | cut -d "." -f 2-)

    if [ "$ver1front" != "$1" ] || [ "$ver2front" != "$2" ]; then
        [ "$ver1front" -gt "$ver2front" ] && return 11
        [ "$ver1front" -lt "$ver2front" ] && return 9

        [ "$ver1front" = "$1" ] || [ -z "$ver1back" ] && ver1back=0
        [ "$ver2front" = "$2" ] || [ -z "$ver2back" ] && ver2back=0
        do_version_check "$ver1back" "$ver2back"
        return $?
    else
        [ "$1" -gt "$2" ] && return 11 || return 9
    fi
}

# Compares two strings and returns 0 if the second is a substring of the first
contains() {
    string="$1"
    substring="$2"
    if [ "${string#*$substring}" != "$string" ]
    then
        return 0    # $substring is in $string
    else
        return 1    # $substring is not in $string
    fi
}