#! /bin/bash

IFS=$'\n'

all_provides() {

    nm "$@" \

    | sed -r -ne 's:^([0-9a-f]+) A __crc_(.+):\1\t\2:p' \

    | sort -k2 -u

}

all_requires() {

    for module in "$@"; do

        set -- $(/usr/sbin/modinfo -F vermagic "$module" | sed -e 's: .*::' -e q)

        /usr/sbin/modprobe --dump-modversions "$module" \

        | awk --non-decimal-data '

            BEGIN { FS = "\t" ; OFS = "\t" }

            {printf("0x%08x\t%s\n", $1, $2)}' \

        | sed -r -e 's:$:\t'"$1"':'

    done \

    | sort -k2 -u

}

if ! [ -e /usr/sbin/modinfo -a -e /usr/sbin/modprobe ]; then

    cat > /dev/null

    exit 0

fi

modules=($(grep -E '/lib/modules/.+\.ko$'))

if [ ${#modules[@]} -gt 0 ]; then

    kernel=$(/usr/sbin/modinfo -F vermagic "${modules[0]}" | sed -e 's: .*::' -e q)

    # get all that kernel provides

    symvers=$(mktemp -t ${0##*/}.XXXXX)

    cat /usr/src/kernels/$kernel/Module.symvers | awk '

        BEGIN { FS = "\t" ; OFS = "\t" }

        { print $2 "\t" $1 }

    ' \

    | sed -r -e 's:$:\t'"$1"':' \

    | sort -u -k2 > $symvers

    # get all that we demands

    reqs=$(mktemp -t ${0##*/}.XXXXX)

    join -t $'\t' -j 2 -v 1 \

            <(all_requires "${modules[@]}") \

            <(all_provides "${modules[@]}") \

    | sort -u -k2 > $reqs

    # get kernel dependencies - kernel(symbol) = 0xHEX

    join -t $'\t' -j2 -o 1.1 1.2 $symvers $reqs \

    | sort -u \

    | awk '

    { FS = "\t" ; OFS = "\t" }

            { print "kernel(" $1 ") = " $2 }

    '

    # get module dependencies - ksym(symbol) = 0xHEX

    join -t $'\t' -j2 -v2 $symvers $reqs \

    | sort -u | awk '

    { FS = "\t" ; OFS = "\t" }

            { print "ksym(" $2 ") = " $1 }

    '

fi