override-builder.sh

#!/bin/bash
# Given a source directory, generate a set of overlay/override RPMs into destdir
set -euo pipefail

fatal() {
    echo 1>&2 "$@"
    exit 1
}

# builds a new RPM and adds it to the testdir's repo
# $1 - name
# $2+ - optional, treated as directive/value pairs
build_rpm() {
    local tmpdir=$(mktemp -d)
    local name=$1; shift
    local srcdir=$(cd $1 && pwd); shift
    # Unset, not zero https://github.com/projectatomic/rpm-ostree/issues/349
    local epoch=""
    local version=1.0
    local release=1
    local arch=$(uname -m)
    local spec=$name.spec

    # write out the header
    cat > $tmpdir/$spec << EOF
Name: $name
Version: $version
Release: $release
License: MIT
${epoch:+Epoch: $epoch}
BuildArch: $arch
Summary: Autogenerated overrides from coreos-override-builder
Provides: rpmostree(override)

%description
%{summary}

%build

%install
cp -pr $srcdir/* %{buildroot}
(cd %{buildroot} && find . -type f) | sed -e 's,^.,,' > files.list

%files -f files.list
EOF

    local outdir=$PWD
    (cd $srcdir
     set -x
     rpmbuild --target $arch -ba $tmpdir/$name.spec \
        --define "_topdir $tmpdir" \
        --define "_sourcedir $tmpdir" \
        --define "_specdir $tmpdir" \
        --define "_builddir $tmpdir/.build" \
        --define "_srcrpmdir $tmpdir" \
        --define "_rpmdir $tmpdir" \
        --define "_buildrootdir $tmpdir"
      mv $tmpdir/*/*.rpm $outdir
    )
    rm "${tmpdir}" -rf
}

srcdir=${1:-}
if test "$#" != 2; then
  fatal "usage: $0 SRCDIR DESTDIR"
fi
shift
outdir=${1:-}
mkdir ${outdir}
echo '{"version": 0}' > ${outdir}/meta.json

rpmdir=${outdir}/rpms

found=0
for d in overlay overrides; do
    if test -d ${srcdir}/rpms/$d; then
        found=1
        rpmd=${rpmdir}/${d}
        mkdir -p $rpmd
        cp -a ${srcdir}/rpms/$d/* ${rpmd}
    fi
done

if test -d "${srcdir}/rootfs/overlay"; then
    found=1
    build_rpm coreos-rootfs-overlay ${srcdir}/rootfs/overlay
    mkdir -p ${rpmdir}/overlay
    mv coreos-rootfs-overlay*.rpm ${rpmdir}/overlay
fi

if test "${found}" = 0; then
    # Verify we're going to remove the right directory
    if test -f "${outdir}/meta.json"; then
        rm "${outdir}" -rf
    fi
    fatal "No rpms/overlay or rootfs/overlay directories found in ${srcdir}"
fi