sh/bash/mount.sh

mo() {
local directory="${1}"
local file
if [ "${directory}" ] ; then
    directory="$(realpath "${directory}")"
    file="${directory}/filesystem.squashfs"
    if mkdir "overlay" ; then
        cd "overlay"
        mkdir {lower,upper,work,mount}
        if mount "${file}" "lower" ; then
            mount -t "overlay" "overlay" "mount" \
-o lowerdir="lower",upperdir="upper",workdir="work"
        fi
        cd ..
    fi
else
    echo "KO: directory?"
fi
}

uo() {
cd "overlay"
if umount "mount" ; then
    rmdir "mount"
    rm --recursive "upper" "work"
    if umount "lower" ; then
        rmdir "lower"
    fi
fi
cd ..
rmdir "overlay"
}


mr() {
for f in "dev" "dev/pts" "proc" "sys" ; do
    mount --bind "/${f}" "overlay/mount/${f}"
done
}

alias cr="\
chroot \
\"overlay/mount\" \
"

alias cru="\
chroot \
--userspec \"1000:1000\" \
\"overlay/mount\" \
"

ur() {
for f in "sys" "proc" "dev/pts" "dev" ; do
    umount --lazy "overlay/mount/${f}"
done
}


mm() {
mount --make-rslave --rbind "/deb" "overlay/mount/deb"
}

um() {
umount --recursive "overlay/mount/deb"
}


ms() {
local directory="${1}"
local level="${2}"
if [ "${directory}" ] ; then
    if mkdir "${directory}" ; then
        [ "${level}" ] || level="18"
        cp overlay/mount/{vmlinuz,initrd.img} "${directory}"
        mksquashfs \
"overlay/mount" "${directory}/filesystem.squashfs" \
-noappend \
-comp "zstd" -Xcompression-level "${level}"
        chown --recursive 1000:1000 "${directory}"
    fi
fi
}