build-docker.sh does not assume PWD=<repo root> (RPi-Distro#302)

* bash variables in build-docker.sh are wrapped by curly brackets

* Ensure presence of config file while running build-docker.sh

* Do not assume that build-docker.sh is run from the repository root directory

* Mount config file in predictable location in docker container

build-docker.sh

@@ -1,36 +1,44 @@
-#!/bin/bash -e
+#!/bin/bash -eu
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
 BUILD_OPTS="$*"
 
 DOCKER="docker"
-set +e
-if ! $DOCKER ps >/dev/null 2>&1; then
+
+if ! ${DOCKER} ps >/dev/null 2>&1; then
 	DOCKER="sudo docker"
 fi
-if ! $DOCKER ps >/dev/null; then
+if ! ${DOCKER} ps >/dev/null; then
 	echo "error connecting to docker:"
-	$DOCKER ps
+	${DOCKER} ps
 	exit 1
 fi
-set -e
 
-if [ -f config ]; then
-	# shellcheck disable=SC1091
-	source config
+CONFIG_FILE=""
+if [ -f "${DIR}/config" ]; then
+	CONFIG_FILE="${DIR}/config"
 fi
 
 while getopts "c:" flag
 do
-	case "$flag" in
+	case "${flag}" in
 		c)
-			# shellcheck disable=SC1090
-			source "$OPTARG"
+			CONFIG_FILE="${OPTARG}"
 			;;
 		*)
 			;;
 	esac
 done
 
+# Ensure that the confguration file is present
+if test -z "${CONFIG_FILE}"; then
+	echo "Configuration file need to be present in '${DIR}/config' or path passed as parameter"
+	exit 1
+else
+	# shellcheck disable=SC1090
+	source "${CONFIG_FILE}"
+fi
+
 CONTAINER_NAME=${CONTAINER_NAME:-pigen_work}
 CONTINUE=${CONTINUE:-0}
 PRESERVE_CONTAINER=${PRESERVE_CONTAINER:-0}
@@ -41,45 +49,50 @@ if [ -z "${IMG_NAME}" ]; then
 exit 1
 fi
 
-CONTAINER_EXISTS=$($DOCKER ps -a --filter name="$CONTAINER_NAME" -q)
-CONTAINER_RUNNING=$($DOCKER ps --filter name="$CONTAINER_NAME" -q)
-if [ "$CONTAINER_RUNNING" != "" ]; then
-	echo "The build is already running in container $CONTAINER_NAME. Aborting."
+CONTAINER_EXISTS=$(${DOCKER} ps -a --filter name="${CONTAINER_NAME}" -q)
+CONTAINER_RUNNING=$(${DOCKER} ps --filter name="${CONTAINER_NAME}" -q)
+if [ "${CONTAINER_RUNNING}" != "" ]; then
+	echo "The build is already running in container ${CONTAINER_NAME}. Aborting."
 	exit 1
 fi
-if [ "$CONTAINER_EXISTS" != "" ] && [ "$CONTINUE" != "1" ]; then
-	echo "Container $CONTAINER_NAME already exists and you did not specify CONTINUE=1. Aborting."
+if [ "${CONTAINER_EXISTS}" != "" ] && [ "${CONTINUE}" != "1" ]; then
+	echo "Container ${CONTAINER_NAME} already exists and you did not specify CONTINUE=1. Aborting."
 	echo "You can delete the existing container like this:"
-	echo "  $DOCKER rm -v $CONTAINER_NAME"
+	echo "  ${DOCKER} rm -v ${CONTAINER_NAME}"
 	exit 1
 fi
 
-$DOCKER build -t pi-gen .
-if [ "$CONTAINER_EXISTS" != "" ]; then
-	trap 'echo "got CTRL+C... please wait 5s"; $DOCKER stop -t 5 ${CONTAINER_NAME}_cont' SIGINT SIGTERM
-	time $DOCKER run --rm --privileged \
+# Modify original build-options to allow config file to be mounted in the docker container
+BUILD_OPTS="$(echo ${BUILD_OPTS:-} | sed -r 's@\-c\s?([^ ]+)@-c /config@')"
+
+${DOCKER} build -t pi-gen "${DIR}"
+if [ "${CONTAINER_EXISTS}" != "" ]; then
+	trap 'echo "got CTRL+C... please wait 5s" && ${DOCKER} stop -t 5 ${CONTAINER_NAME}_cont' SIGINT SIGTERM
+	time ${DOCKER} run --rm --privileged \
+		--volume "${CONFIG_FILE}":/config:ro \
 		--volumes-from="${CONTAINER_NAME}" --name "${CONTAINER_NAME}_cont" \
 		pi-gen \
 		bash -e -o pipefail -c "dpkg-reconfigure qemu-user-static &&
 	cd /pi-gen; ./build.sh ${BUILD_OPTS} ;
 	rsync -av work/*/build.log deploy/" &
 	wait "$!"
 else
-	trap 'echo "got CTRL+C... please wait 5s"; $DOCKER stop -t 5 ${CONTAINER_NAME}' SIGINT SIGTERM
-	time $DOCKER run --name "${CONTAINER_NAME}" --privileged \
+	trap 'echo "got CTRL+C... please wait 5s" && ${DOCKER} stop -t 5 ${CONTAINER_NAME}' SIGINT SIGTERM
+	time ${DOCKER} run --name "${CONTAINER_NAME}" --privileged \
+		--volume "${CONFIG_FILE}":/config:ro \
 		pi-gen \
 		bash -e -o pipefail -c "dpkg-reconfigure qemu-user-static &&
 	cd /pi-gen; ./build.sh ${BUILD_OPTS} &&
 	rsync -av work/*/build.log deploy/" &
 	wait "$!"
 fi
 echo "copying results from deploy/"
-$DOCKER cp "${CONTAINER_NAME}":/pi-gen/deploy .
+${DOCKER} cp "${CONTAINER_NAME}":/pi-gen/deploy .
 ls -lah deploy
 
 # cleanup
-if [ "$PRESERVE_CONTAINER" != "1" ]; then
-	$DOCKER rm -v "$CONTAINER_NAME"
+if [ "${PRESERVE_CONTAINER}" != "1" ]; then
+	${DOCKER} rm -v "${CONTAINER_NAME}"
 fi
 
 echo "Done! Your image(s) should be in deploy/"