contrib/jenkins: add script to build in docker

Related: SYS#6356

contrib/Dockerfile

@@ -0,0 +1,38 @@
+ARG	REGISTRY=docker.io
+FROM	${REGISTRY}/debian/eol:jessie-slim
+# Arguments used after FROM must be specified again
+ARG	UID
+
+RUN	( echo "deb http://archive.debian.org/debian jessie main"; \
+	  echo "deb http://archive.debian.org/debian-security jessie/updates main" ) \
+		> /etc/apt/sources.list
+
+RUN	apt-get update && \
+	apt-get install -y --no-install-recommends \
+		ca-certificates \
+		build-essential \
+		chrpath \
+		cpio \
+		diffstat \
+		file \
+		gawk \
+		git \
+		locales \
+		make \
+		python \
+		python3 \
+		texinfo \
+		wget \
+		&& \
+	apt-get clean
+
+# Disable DST Root CA X3
+# https://letsencrypt.org/docs/dst-root-ca-x3-expiration-september-2021/
+RUN	sed -i '/^mozilla\/DST_Root_CA_X3.crt$/ s/^/!/' /etc/ca-certificates.conf && \
+	update-ca-certificates
+
+RUN	echo "en_US.UTF-8 UTF-8" > /etc/locale.gen && \
+	locale-gen
+
+RUN	useradd --uid=${UID} -m user
+USER	user

contrib/jenkins.sh

@@ -0,0 +1,38 @@
+#!/bin/sh -e
+DOCKER_IMG="sysmocom-system-images-oe"
+
+if [ -z "$SSH_AUTH_SOCK" ]; then
+	echo "ERROR: SSH_AUTH_SOCK is empty!"
+	exit 1
+fi
+
+set -x
+cd "$(dirname "$(realpath "$0")")/.."
+
+docker build \
+	--build-arg UID=$(id -u) \
+	-t "$DOCKER_IMG":latest \
+	contrib
+
+docker run \
+	-it \
+	--rm \
+	-e SSH_AUTH_SOCK=/ssh-agent \
+	-v "$(readlink -f "$SSH_AUTH_SOCK")":/ssh-agent \
+	-v "$PWD:/system-images" \
+	"$DOCKER_IMG" \
+	sh -e -x -c "
+		export LC_ALL=en_US.UTF-8
+		cd /system-images
+
+		make clean-all || true
+		make build-all
+
+		make sysmobts-upload FEED_NAME=\"201705-nightly\"
+		make sysmobts2100-upload FEED_NAME=\"201705-nightly\"
+		make oc2g-upload FEED_NAME=\"201705-nightly\"
+		make sysmocom-alix-upload FEED_NAME=\"201705-nightly\"
+		make sysmocom-apu2-upload FEED_NAME=\"201705-nightly\"
+
+		make clean-all
+	"