docker: add a convenience script

glasgow-docker.sh

+#!/bin/bash
+set -eu
+
+image="docker.agsys.io/attie/glasgow:latest"
+cache_volume="glasgow-cache"
+
+#src_dir=".../path/to/glasgow/repo"
+
+if [ ${#} -eq 1 ] && [ "${1}" == "pull" ]; then
+	docker pull "${image}"
+	exit $?
+fi
+
+args=()
+args+=( run --rm -it --privileged )
+args+=( -v /dev/bus/usb:/dev/bus/usb )
+args+=( -v ${cache_volume}:/home/user/.cache/GlasgowEmbedded )
+
+if [ "${PWD}" == "${src_dir:-}" ]; then
+	args+=( -v "${PWD}:/opt/glasgow/" )
+fi
+
+if [ ${#} -eq 1 ] && [ "${1}" == "--help" ]; then
+	cat <<-EOF >&2
+	NOTE: You are using glasgow-in-docker, some things might not work as you'd expect (like
+	      USB hotplug support)... The following basic modes are also available to you:
+
+	  ${0##*/} pull         : retrieve an update docker image
+	  ${0##*/} cache-clear  : remove the cache volume
+	  ${0##*/} bash         : enter a shell inside a new container
+
+	---
+	EOF
+	args=( run --rm "${image}" "${@}" )
+
+elif [ ${#} -eq 1 ] && [ "${1}" == "pull" ]; then
+	args=( pull "${image}" )
+
+elif [ ${#} -eq 1 ] && [ "${1}" == "cache-clear" ]; then
+	echo "Removing volume '${cache_volume}'..." >&2
+	args=( volume rm "${cache_volume}" )
+
+elif [ ${#} -eq 1 ] && [ "${1}" == "bash" ]; then
+	args+=( --entrypoint '' "${image}" "${@}" )
+
+else
+	# normal operation
+	args+=( "${image}" "${@}" )
+fi
+
+docker "${args[@]}"
+exit ${?}