shell script to search about deadlink

deadlink.sh

#!/bin/sh

deadlink() {
        local NO_ABS=false
        local NO_REL=false
        while [ $# -gt 0 ]; do
                case "$1" in
                ('-h'|'--help')
                        echo "Usage: $0 [--na|--no-absolute]|[--nr|--no-relative] [--] <directory>";
                        exit 0;
                ;;
                ('--na'|'--no-abs'*) shift; NO_ABS=true ;;
                ('--nr'|'--no-rel'*) shift ; NO_REL=true ;;
                ('--') shift; break ;;
                ('-'*) echo >&2 "Bad option $1"; exit 1 ;;
                *) break;
                esac
        done
        local file="" from="" link=""
        while [ $# -gt 0 ]; do
                find "$1" -type l -printf 'p %P\nl %l\n' | {
                while read -r type line; do
                        case "$type" in
                        (p)
                                file="$line"
                                from="$(dirname "$file")"
                        ;;
                        (l)
                                link="$line"
                                if case "$link" in
                                        ('/'*) false;;
                                        (*) true;;
                                esac; then
                                        ${NO_REL:-false} && continue
                                        link="$1/$from/$link"
                                else
                                        ${NO_ABS:-false} && continue
                                fi
                                [ ! -e "$link" ] && echo "!! $1/$file -> $link"
                        ;;
                        esac
                done
                }
                shift;
        done
}
deadlink "$@"