Set version 1.0.0, and add RPM packaging.

configure.ac

 AC_PREREQ(2.68)
 AC_COPYRIGHT([Copyright (c) 2019 UPLEX - Nils Goroll Systemoptimierung])
-AC_INIT([libvmod-file], [trunk], [varnish-support@uplex.de], [vmod-file])
+AC_INIT([libvmod-file], [1.0.0], [varnish-support@uplex.de], [vmod-file])
 AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_SRCDIR(src/vmod_file.vcc)
 AM_CONFIG_HEADER(config.h)

pkg/rpm/pkg

+#! /bin/bash -ex
+
+# Build script for a VMOD file el7 RPM
+# to be run in the rpmbuild/centos7 docker container.
+
+# Env variables VERSION and RELEASE MUST be set in the docker invocation.
+# DIST is set by the rpmbuild/centos7 container.
+
+# The directory mounted to /srv MUST contain these files:
+# - this script (named pkg)
+# - VMOD file tarball (vmod-file-$VERSION.tar.gz)
+# - RPM spec file (vmod-file.spec)
+# - yum repo config for varnish66@packagecloud (varnishcache_varnish66.repo)
+#   (see https://packagecloud.io/varnishcache/varnish66/install#manual-rpm)
+
+# So this is a sample docker invocation:
+#
+# $ docker run -t -v $PWD:/srv -e VERSION=1.2.3 -e RELEASE=4711 \
+#	rpmbuild/centos7 /srv/pkg
+
+# At the end of the run, binary, source and debuginfo RPMs are in the
+# directory mounted to /srv.
+
+if [ -z $VERSION ]; then
+   echo "Env variable VERSION MUST be set"
+   exit 1
+fi
+
+if [ -z $RELEASE ]; then
+   echo "Env variable RELEASE MUST be set"
+   exit 1
+fi
+
+# delete the peculiar macros from the rpmbuild/centos7 image
+rm /home/builder/.rpmmacros
+
+# set up the build environment
+cd /home/builder
+mkdir -p rpmbuild/{BUILD,BUILDROOT,RPMS,SOURCES,SPECS,SRPMS}
+cp /srv/vmod-file.spec rpmbuild/SPECS
+cp /srv/vmod-file-${VERSION}.tar.gz rpmbuild/SOURCES
+
+# install epel7 repo
+sudo yum install -y -q \
+     https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
+
+# set up varnish repo
+sudo cp /srv/varnishcache_varnish66.repo /etc/yum.repos.d/
+
+sudo yum -q makecache -y --disablerepo='*' --enablerepo='varnishcache_varnish66'
+
+# build requirements
+sudo yum install -y -q \
+     varnish-devel pkgconfig make gcc gcc-c++ python-docutils
+
+# build RPMs
+rpmbuild -ba -D "dist .${DIST}" \
+         -D "_version ${VERSION}" \
+         -D "_release ${RELEASE}" \
+         rpmbuild/SPECS/vmod-file.spec
+
+sudo cp rpmbuild/RPMS/*/* /srv
+sudo cp rpmbuild/SRPMS/* /srv

pkg/rpm/varnishcache_varnish66.repo

+[varnishcache_varnish66]
+name=varnishcache_varnish66
+baseurl=https://packagecloud.io/varnishcache/varnish66/el/7/$basearch
+repo_gpgcheck=1
+gpgcheck=0
+enabled=1
+gpgkey=https://packagecloud.io/varnishcache/varnish66/gpgkey
+sslverify=1
+sslcacert=/etc/pki/tls/certs/ca-bundle.crt
+metadata_expire=300
+
+[varnishcache_varnish66-source]
+name=varnishcache_varnish66-source
+baseurl=https://packagecloud.io/varnishcache/varnish66/el/7/SRPMS
+repo_gpgcheck=1
+gpgcheck=0
+enabled=1
+gpgkey=https://packagecloud.io/varnishcache/varnish66/gpgkey
+sslverify=1
+sslcacert=/etc/pki/tls/certs/ca-bundle.crt
+metadata_expire=300

pkg/rpm/vmod-file.spec

+# -D MUST pass in _version and _release, and SHOULD pass in dist.
+
+Summary: Varnish Module for reading files that may be updated at intervals
+Name: vmod-file
+Version: %{_version}
+Release: %{_release}%{?dist}
+License: BSD
+Group: System Environment/Daemons
+URL: https://code.uplex.de/uplex-varnish/libvmod-file
+Source0: %{name}-%{version}.tar.gz
+
+# varnish from varnish66 at packagecloud
+# This is the Requires for VMOD ABI compatibility with VRT >= 13.0.
+Requires: varnishd(vrt)%{?_isa} >= 13
+
+BuildRequires: varnish-devel >= 6.6.0
+BuildRequires: pkgconfig
+BuildRequires: make
+BuildRequires: gcc
+BuildRequires: gcc-c++
+BuildRequires: python-docutils >= 0.6
+
+# git builds
+#BuildRequires: automake
+#BuildRequires: autoconf
+#BuildRequires: autoconf-archive
+#BuildRequires: libtool
+#BuildRequires: python-docutils >= 0.6
+
+Provides: vmod-file, vmod-file-debuginfo
+
+%description
+VMOD file is a Varnish module for reading the contents of a file and
+caching its contents, returning the contents for use in the Varnish
+Configuration Language (VCL), and checking if the file has changed
+after specified time intervals elapse.
+
+%prep
+%setup -q -n %{name}-%{version}
+
+%build
+
+# if this were a git build
+# ./autogen.sh
+
+%configure
+
+make -j
+
+%check
+
+make -j check
+
+%install
+
+make install DESTDIR=%{buildroot}
+
+# Only use the version-specific docdir created by %doc below
+rm -rf %{buildroot}%{_docdir}
+
+# None of these for fedora/epel
+find %{buildroot}/%{_libdir}/ -name '*.la' -exec rm -f {} ';'
+find %{buildroot}/%{_libdir}/ -name '*.a' -exec rm -f {} ';'
+
+%clean
+rm -rf %{buildroot}
+
+%files
+%defattr(-,root,root,-)
+%{_libdir}/varnish*/vmods/
+%{_mandir}/man3/*.3*
+%doc README.rst COPYING LICENSE
+
+%post
+/sbin/ldconfig
+
+%changelog
+* Wed Jan 26 2022 Geoff Simmons <geoff@uplex.de> - %{_version}-%{_release}
+- Require VRT 13.0, compatible with Varnish 6.6
+
+* Tue Oct 8 2019 Geoff Simmons <geoff@uplex.de> - 0.2.3-1
+- Require VRT 10.0, compatible with Varnish 6.3