#!/bin/sh

USE_ALT_MODS_DIR=false
OPENIBD_COMMANDS="start force-start stop force-stop restart force-restart status"
# An alternative version of /lib/modules to load modules from.
# Typically from a container host:
ALT_MODS_DIR="/host/lib/modules"
MLNXOFACTL_SHARED="${MLNXOFACTL_SHARED:-}" # For internal use


me=${0##*/}

usage() {
	cat <<EOF
$me: $OPENIBD_SCRIPT wrapper

Usage: $me [--alt-mods] <command>

  -a | --alt-mods    Use modules from alternative location: $ALT_MODS_DIR
  <command>:    $OPENIBD_COMMANDS
EOF
}

err() {
	echo "$me: Error: $*" >&2
}

check_valid_command() {
	local cmd=`echo "$1" | tr -d -c 'a-z-'`
	echo "$OPENIBD_COMMANDS" | grep -q -w "$cmd"
}

ORIG_CMDLINE="$*"
# Re-run script in a separate filesystem namespace:
do_unshare() {
	if ! $USE_ALT_MODS_DIR; then return; fi
	if [ "$MLNXOFACTL_SHARED" != '' ]; then return; fi

	export MLNXOFACTL_SHARED="USE_ALT_MODS_DIR"
	exec unshare --mount "$0" $ORIG_CMDLINE # FIXME: bash arrays?
}

run_with_host_modules() {
	if ! $USE_ALT_MODS_DIR; then return; fi
	mount -r -o bind "$ALT_MODS_DIR" /lib/modules
}

set_openibd() {
	OPENIBD_SCRIPT="/etc/init.d/openibd"
	if [ ! -x "$OPENIBD_SCRIPT" -a -x /etc/init.d/mlnx-en.d ]; then
		OPENIBD_SCRIPT="/etc/init.d/mlnx-en.d"
	fi
}

set -e

getopt_tmp=$(getopt -o ai --long alt-mods,help -n "$me" -- "$@")
eval set -- "$getopt_tmp"
while true; do
	case "$1" in
	-h | --help) usage; exit 0;;
	-a | --alt-mods) USE_ALT_MODS_DIR=true;;
	--)
		shift
		break
		;;
	*)
		echo "$0: Error parsing command line" >&2
		exit 1
		;;
	esac
	shift
done

do_unshare

command="$1"
if ! check_valid_command "$command"; then
	err "Invalid command '$command'. Try one of $OPENIBD_COMMANDS."
	usage
	exit 2
fi

set_openibd

if $USE_ALT_MODS_DIR; then
	run_with_host_modules
fi

$OPENIBD_SCRIPT "$command"