diff --git a/hack/dind b/hack/dind new file mode 100644 index 0000000000..5d606ed42f --- /dev/null +++ b/hack/dind @@ -0,0 +1,56 @@ +#!/bin/bash + +# First, make sure that cgroups are mounted correctly. +CGROUP=/sys/fs/cgroup + +[ -d $CGROUP ] || + mkdir $CGROUP + +mountpoint -q $CGROUP || + mount -n -t tmpfs -o uid=0,gid=0,mode=0755 cgroup $CGROUP || { + echo "Could not make a tmpfs mount. Did you use -privileged?" + exit 1 + } + +# Mount the cgroup hierarchies exactly as they are in the parent system. +for SUBSYS in $(cut -d: -f2 /proc/1/cgroup) +do + [ -d $CGROUP/$SUBSYS ] || mkdir $CGROUP/$SUBSYS + mountpoint -q $CGROUP/$SUBSYS || + mount -n -t cgroup -o $SUBSYS cgroup $CGROUP/$SUBSYS +done + +# Note: as I write those lines, the LXC userland tools cannot setup +# a "sub-container" properly if the "devices" cgroup is not in its +# own hierarchy. Let's detect this and issue a warning. +grep -q :devices: /proc/1/cgroup || + echo "WARNING: the 'devices' cgroup should be in its own hierarchy." +grep -qw devices /proc/1/cgroup || + echo "WARNING: it looks like the 'devices' cgroup is not mounted." + +# Now, close extraneous file descriptors. +pushd /proc/self/fd +for FD in * +do + case "$FD" in + # Keep stdin/stdout/stderr + [012]) + ;; + # Nuke everything else + *) + eval exec "$FD>&-" + ;; + esac +done +popd + +# If we were given a PORT environment variable, start as a simple daemon; +# otherwise, spawn a shell as well +if [ "$PORT" ] +then + exec docker -d -H 0.0.0.0:$PORT +else + + docker -d & + exec bash +fi