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mboersmamboersma
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fix(builder): update d-in-d wrapper for newer CoreOS
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Lines changed: 105 additions & 69 deletions

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‎builder/rootfs/bin/entry‎

Lines changed: 105 additions & 69 deletions
Original file line numberDiff line numberDiff line change
@@ -7,83 +7,119 @@ fi
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# START jpetazzo/dind wrapper
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# First, make sure that cgroups are mounted correctly.
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CGROUP=/sys/fs/cgroup
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# DinD: a wrapper script which allows docker to be run inside a docker container.
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# Original version by Jerome Petazzoni <jerome@docker.com>
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# See the blog post: https://blog.docker.com/2013/09/docker-can-now-run-within-docker/
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#
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# This script should be executed inside a docker container in privilieged mode
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# ('docker run --privileged', introduced in docker 0.6).
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[ -d $CGROUP ] ||
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mkdir $CGROUP
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# Usage: dind CMD [ARG...]
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mountpoint -q $CGROUP ||
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mount -n -t tmpfs -o uid=0,gid=0,mode=0755 cgroup $CGROUP || {
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echo "Could not make a tmpfs mount. Did you use -privileged?"
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exit 1
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}
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# apparmor sucks and Docker needs to know that it's in a container (c) @tianon
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export container=docker
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# as of docker 1.8, cgroups will be mounted in the container
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if ! mountpoint -q /sys/fs/cgroup; then
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# First, make sure that cgroups are mounted correctly.
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CGROUP=/cgroup
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mkdir -p "$CGROUP"
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if ! mountpoint -q "$CGROUP"; then
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mount -n -t tmpfs -o uid=0,gid=0,mode=0755 cgroup $CGROUP || {
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echo >&2 'Could not make a tmpfs mount. Did you use --privileged?'
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exit 1
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}
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fi
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# Mount the cgroup hierarchies exactly as they are in the parent system.
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for HIER in $(cut -d: -f2 /proc/1/cgroup); do
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# The following sections address a bug which manifests itself
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# by a cryptic "lxc-start: no ns_cgroup option specified" when
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# trying to start containers within a container.
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# The bug seems to appear when the cgroup hierarchies are not
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# mounted on the exact same directories in the host, and in the
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# container.
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SUBSYSTEMS="${HIER%name=*}"
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# If cgroup hierarchy is named(mounted with "-o name=foo") we
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# need to mount it in $CGROUP/foo to create exect same
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# directoryes as on host. Else we need to mount it as is e.g.
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# "subsys1,subsys2" if it has two subsystems
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# Named, control-less cgroups are mounted with "-o name=foo"
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# (and appear as such under /proc/<pid>/cgroup) but are usually
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# mounted on a directory named "foo" (without the "name=" prefix).
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# Systemd and OpenRC (and possibly others) both create such a
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# cgroup. So just mount them on directory $CGROUP/foo.
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OHIER=$HIER
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HIER="${HIER#*name=}"
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mkdir -p "$CGROUP/$HIER"
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if ! mountpoint -q "$CGROUP/$HIER"; then
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mount -n -t cgroup -o "$OHIER" cgroup "$CGROUP/$HIER"
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fi
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if [ -d /sys/kernel/security ] && ! mountpoint -q /sys/kernel/security
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then
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mount -t securityfs none /sys/kernel/security || {
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echo "Could not mount /sys/kernel/security."
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echo "AppArmor detection and -privileged mode might break."
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}
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# Likewise, on at least one system, it has been reported that
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# systemd would mount the CPU and CPU accounting controllers
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# (respectively "cpu" and "cpuacct") with "-o cpuacct,cpu"
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# but on a directory called "cpu,cpuacct" (note the inversion
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# in the order of the groups). This tries to work around it.
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if [ "$HIER" = 'cpuacct,cpu' ]; then
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ln -s "$HIER" "$CGROUP/cpu,cpuacct"
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fi
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# If hierarchy has multiple subsystems, in /proc/<pid>/cgroup
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# we will see ":subsys1,subsys2,subsys3,name=foo:" substring,
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# we need to mount it to "$CGROUP/foo" and if there were no
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# name to "$CGROUP/subsys1,subsys2,subsys3", so we must create
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# symlinks for docker daemon to find these subsystems:
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# ln -s $CGROUP/foo $CGROUP/subsys1
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# ln -s $CGROUP/subsys1,subsys2,subsys3 $CGROUP/subsys1
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if [ "$SUBSYSTEMS" != "${SUBSYSTEMS//,/ }" ]; then
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SUBSYSTEMS="${SUBSYSTEMS//,/ }"
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for SUBSYS in $SUBSYSTEMS
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do
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ln -s "$CGROUP/$HIER" "$CGROUP/$SUBSYS"
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done
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fi
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done
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fi
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30-
# Mount the cgroup hierarchies exactly as they are in the parent system.
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for SUBSYS in $(cut -d: -f2 /proc/1/cgroup)
32-
do
33-
[ -d $CGROUP/$SUBSYS ] || mkdir $CGROUP/$SUBSYS
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mountpoint -q $CGROUP/$SUBSYS ||
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mount -n -t cgroup -o $SUBSYS cgroup $CGROUP/$SUBSYS
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# The two following sections address a bug which manifests itself
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# by a cryptic "lxc-start: no ns_cgroup option specified" when
39-
# trying to start containers withina container.
40-
# The bug seems to appear when the cgroup hierarchies are not
41-
# mounted on the exact same directories in the host, and in the
42-
# container.
43-
44-
# Named, control-less cgroups are mounted with "-o name=foo"
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# (and appear as such under /proc/<pid>/cgroup) but are usually
46-
# mounted on a directory named "foo" (without the "name=" prefix).
47-
# Systemd and OpenRC (and possibly others) both create such a
48-
# cgroup. To avoid the aforementioned bug, we symlink "foo" to
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# "name=foo". This shouldn't have any adverse effect.
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echo $SUBSYS | grep -q ^name= && {
51-
NAME=$(echo $SUBSYS | sed s/^name=//)
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ln -s $SUBSYS $CGROUP/$NAME
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}
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# Likewise, on at least one system, it has been reported that
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# systemd would mount the CPU and CPU accounting controllers
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# (respectively "cpu" and "cpuacct") with "-o cpuacct,cpu"
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# but on a directory called "cpu,cpuacct" (note the inversion
59-
# in the order of the groups). This tries to work around it.
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[ $SUBSYS = cpuacct,cpu ] && ln -s $SUBSYS $CGROUP/cpu,cpuacct
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done
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if [ -d /sys/kernel/security ] && ! mountpoint -q /sys/kernel/security; then
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mount -t securityfs none /sys/kernel/security || {
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echo >&2 'Could not mount /sys/kernel/security.'
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echo >&2 'AppArmor detection and --privileged mode might break.'
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}
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fi
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# Note: as I write those lines, the LXC userland tools cannot setup
64105
# a "sub-container" properly if the "devices" cgroup is not in its
65106
# own hierarchy. Let's detect this and issue a warning.
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grep -q :devices: /proc/1/cgroup ||
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echo "WARNING: the 'devices' cgroup should be in its own hierarchy."
68-
grep -qw devices /proc/1/cgroup ||
69-
echo "WARNING: it looks like the 'devices' cgroup is not mounted."
70-
71-
# Now, close extraneous file descriptors.
72-
pushd /proc/self/fd >/dev/null
73-
for FD in *
74-
do
75-
case "$FD" in
76-
# Keep stdin/stdout/stderr
77-
[012])
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;;
79-
# Nuke everything else
80-
*)
81-
eval exec "$FD>&-"
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;;
83-
esac
84-
done
85-
popd >/dev/null
107+
if ! grep -q :devices: /proc/1/cgroup; then
108+
echo >&2 'WARNING: the "devices" cgroup should be in its own hierarchy.'
109+
fi
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if ! grep -qw devices /proc/1/cgroup; then
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echo >&2 'WARNING: it looks like the "devices" cgroup is not mounted.'
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fi
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87-
# END jpetazzo/dind wrapper
114+
# Mount /tmp (conditionally)
115+
if ! mountpoint -q /tmp; then
116+
mount -t tmpfs none /tmp
117+
fi
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89-
exec $@
119+
if [ $# -gt 0 ]; then
120+
exec "$@"
121+
fi
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123+
echo >&2 'ERROR: No command specified.'
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echo >&2 'You probably want to run hack/make.sh, or maybe a shell?'
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# END jpetazzo/dind wrapper

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