#!/bin/bash

# Copyright 2017 Matthew Thode
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

if [[ "${DIB_DEBUG_TRACE:-0}" -gt 0 ]]; then
    set -x
fi
set -eu
set -o pipefail

# make /dev/shm dir if it doesn't exist
# mount tmpfs and chown it
# existing programs could be using /dev/shm
#  This means it cannot be moved or backed
#  up as a copy easily.  The only remaining
#  option is to move the link if it exists
#  as a link.  Existing programs will still
#  hold the file handle of the original
#  location open and new programs can use
#  the fixed /dev/shm.
[[ -e /run/lock/shm_fixed ]] && exit 0  # shm has already been fixed
if [[ ! -d /dev/shm ]]; then
    if [[ ! -e /dev/shm ]]; then
        if [[ -L /dev/shm ]]; then
            mv /dev/shm /dev/shm.orig
        fi
        mkdir /dev/shm
    fi
fi
mount -t tmpfs none /dev/shm
chmod 1777 /dev/shm
mkdir -p /run/lock
touch /run/lock/shm_fixed