FROM debian:jessie

# Why bother with this whole song and dance?  qemu-img versions >=2.2.1 have a
# "bug" which causes the generated VHD files to be improperly formatted for
# running on Azure: https://bugs.launchpad.net/qemu/+bug/1490611
# 
# Since Alpine has only qemu-img >= 2.4.1 in its apk index, we cannot use
# Alpine.
RUN apt-get update && \
    apt-get install -y qemu-utils

# If version changes in distributed packages, this build is busted.  Sanity check.
RUN qemu-img --version
RUN qemu-img --version | awk '{ if ($3 != "2.1.2,") exit 1; }'

ENTRYPOINT ["qemu-img", "convert", "-f", "raw", "-O", "vpc", "-o", "subformat=fixed"]