replace docker-x binary with a script that downloads on demand

Signed-off-by: Justin Cormack <justin.cormack@unikernel.com>

alpine/Dockerfile

@@ -27,7 +27,7 @@ COPY packages/mdnstool/mdnstool /sbin/
 COPY packages/mdnstool/etc /etc/
 COPY packages/docker/docker /usr/bin/
 COPY packages/docker/etc /etc/
-#COPY packages/docker-x/docker-x /usr/bin/
+COPY packages/docker-x/get-docker-x /usr/bin/
 COPY packages/diagnostics/diagnostics /usr/bin/
 COPY packages/diagnostics/etc /etc/
 COPY packages/automount/etc /etc/

alpine/packages/Makefile

@@ -2,10 +2,8 @@ all:
 	$(MAKE) -C 9pudc
 	$(MAKE) -C mdnstool
 	$(MAKE) -C docker
-	$(MAKE) -C docker-x
 
 clean:
 	$(MAKE) -C 9pudc clean
 	$(MAKE) -C mdnstool clean
 	$(MAKE) -C docker clean
-	$(MAKE) -C docker-x clean

alpine/packages/docker-x/.gitignore

@@ -1 +0,0 @@
-docker-x

alpine/packages/docker-x/Makefile

@@ -1,8 +0,0 @@
-all: docker-x
-
-docker-x:
-	curl -L https://experimental.docker.com/builds/Linux/x86_64/docker-latest > docker-x
-	chmod +x docker-x
-
-clean:
-	rm -f docker-x

alpine/packages/docker-x/get-docker-x

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+OS=$(uname -s)
+ARCH=$(uname -m)
+
+curl -L https://experimental.docker.com/builds/${OS}/${ARCH}/docker-latest > /usr/bin/docker-x && chmod +x /usr/bin/docker-x

alpine/packages/docker/etc/init.d/docker

@@ -4,6 +4,9 @@ export DOCKER_RAMDISK="true"
 
 DOCKER_OPTS="${DOCKER_OPTS:--s aufs}"
 command="${DOCKER_BINARY:-/usr/bin/docker}"
+
+[ ! -f ${DOCKER_BINARY} ] && [ "${DOCKER_BINARY}" = "/usr/bin/docker-x" ] && get-docker-x
+
 pidfile="${DOCKER_PIDFILE:-/run/${RC_SVCNAME}.pid}"
 command_args="daemon -p \"${pidfile}\" ${DOCKER_OPTS}"
 DOCKER_LOGFILE="${DOCKER_LOGFILE:-/var/log/${RC_SVCNAME}.log}"