#!/bin/sh
set -eu

# Docker exposes the filesystem source after the separator in mountinfo.
# A bind mount whose host source is an ext4 filesystem on zram retains that
# source; a plain host directory on the HDD must not pass this check.
awk '
    $5 == "/hw/tests/tmp" {
        for (i = 6; i <= NF - 2; i++) {
            if ($i == "-" && $(i + 1) == "ext4" && $(i + 2) ~ /^\/dev\/zram[0-9]+$/)
                found = 1
        }
    }
    END { exit !found }
' /proc/self/mountinfo