# This Docker image can change from one build to another, because the upstream
# Debian/Ubuntu package index is continuously updated and we have to run
# `apt-get update` in here.
#
# The only way to make this a part of our reproducible build system is to build
# it once, upload it to Docker Hub and make sure it's being pulled regularly so
# it's not deleted after 6 months of inactivity.

FROM arm64v8/ubuntu:20.04

SHELL ["/bin/bash", "-c"]

ARG QEMU_NAME
ARG QEMU_DIR

# We need the host's registered binfmt_misc "interpreter" inside the container,
# for that transparent virtualisation to work.
COPY $QEMU_NAME $QEMU_DIR

# We delete the static Qemu binary when we're done with it, because it might
# not run on other systems. Let the child image copy it again.
ENV DEBIAN_FRONTEND=noninteractive TZ="Etc/UTC"
RUN apt-get -qq update \
 && apt-get -qq -y install build-essential git &>/dev/null \
 && apt-get -qq clean \
 && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* "${QEMU_DIR}/${QEMU_NAME}"