1 files changed, 48 insertions, 0 deletions
diff --git a/ec2-init-appliance-ebs-volume-mount.sh b/ec2-init-appliance-ebs-volume-mount.sh
new file mode 100755
index 00000000..7106b353
--- /dev/null
+++ b/ec2-init-appliance-ebs-volume-mount.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+
+if [ -n "$EBSMOUNT_DEBUG" ]
+then
+    do="echo"
+    mktemp_args="-u"
+else
+    do=""
+    mktemp_args=""
+fi
+
+if [ "$#" -lt 2 ]
+then
+	echo "Usage: $0 <EBS device> <path> [<path> [<path>...]]"
+	exit 1
+fi
+
+ebs_volume_device="$1"
+shift
+
+canonicalise_dir() {
+    dirname="$1"
+    echo "${dirname}" | sed -e 's/[^a-zA-Z0-9]/_/g'
+}
+
+# The blkid call will detect whether there's already a filesystem on the EBS volume
+if [ -n "$(blkid -p -o udev "${ebs_volume_device}")" ]
+then
+    $do mkfs.ext3 "${ebs_volume_device}"
+fi
+
+tmpdir="$(mktemp -d $mktemp_args --tmpdir=/var/run/ec2-init)"
+$do mount ${ebs_volume_device} ${tmpdir}
+
+for dir in "$@"
+do
+    ebsdir="${tmpdir}/$(canonicalise_dir "${dir}")"
+    if [ ! -d "${ebsdir}" ]
+    then
+        # We bootstrap the storage with the existing data
+        $do mkdir "${ebsdir}"
+        $do cp -a ${dir} "${ebsdir}"
+        $do chown --reference "${dir}" "${ebsdir}"
+        $do chmod --reference "${dir}" "${ebsdir}"
+    fi
+    # Finally, we mount it on top of the old directory.
+    $do mount --bind "${ebsdir}" "${dir}"
+done