#! /bin/bash

usage() {
    echo "Usage: ${0##*/} {dir} < Module.symvers"
    exit $1
}

[ $# -eq 1 ] || usage 1
dir=$1

tmpdir=$(mktemp -dt ${0##*/}.XXXXXXXXXX)
trap "rm -rf $tmpdir" EXIT

split_into_sets() {
    local dir=$1

    awk '
	  { set = gensub(/\/[^\/]+$/, "", "", $3)
	    sets[set] = sets[set] $0 "\n"
	  }
    END   {
	    for (set in sets) {
	      filename = gensub(/\//, "_", "g", set)
	      printf "%s", sets[set] > dir "/" filename
	    }
	  }
    ' dir="$dir"
}

sort -k2 \
| split_into_sets "$tmpdir"

shopt -s nullglob
set -- $tmpdir/*
if [ $# -ne 0 ]; then
    md5sum "$@" \
    | while read md5sum set; do
	cp $set $dir/${set##*/}.${md5sum:0:16}
    done
fi