kernel

#!/bin/bash
#

# Utilities for kernel module management.
#
function mod-recursive-rdepends()
{
    if test $# -gt 0; then
        declare -p MOD_RECURSE_DEPTH > /dev/null 2>&1 \
            && MOD_RECURSE_DEPTH=$(( ${MOD_RECURSE_DEPTH} + 1 )) \
                || export MOD_RECURSE_DEPTH=0
        declare -p MOD_USERS  > /dev/null 2>&1 || eval "$(mod-stat)"
        export MOD_USERS

        local OUT=""

        for mod in ${MOD_USERS[$1]}; do
            APPEND="$(mod-recursive-rdepends ${mod})"
            test -n "${OUT}" \
                && OUT="${OUT} ${APPEND}" \
                    || OUT="${APPEND}"
        done

        test -n "${OUT}" && OUT="${OUT} $1" || OUT="$1"

        test $MOD_RECURSE_DEPTH -eq 0 \
            && unset MOD_RECURSE_DEPTH MOD_USERS \
                || MOD_RECURSE_DEPTH=$(( ${MOD_RECURSE_DEPTH} - 1 ))
        echo "${OUT}"
    else
        echo "Usage: mod-recursive-rdepends MODNAME" > /dev/stderr
        return 1
    fi
}


function mod-stat()
{
    echo 'declare -A MOD_USERS'
    cut -d ' ' -f 1,4 /proc/modules | sed -e 's#,# #g;s#^\([^ ]\+\)\x20\+\(.\+\)$#MOD_USERS[\1]="\2"#g;s#="-"#=""#g;s# "$#"#g'
}

## Determine the number of users of the target module.
#
# \param	$1	Module to count users for.
#
# \returns	The number of users of the target module.
function mod-num-users()
{
    declare -pA MOD_USERS > /dev/null 2>&1 || eval "$(mod-stat)"
    local -a USERS
    USERS=( ${MOD_USERS[$1]} )
    echo ${#USERS[*]}
}