#!/bin/sh
#
#       Based on a example file to build /etc/init.d/ scripts,
#        written by Miquel van Smoorenburg <miquels@cistron.nl>
#        and later modified by Ian Murdock <imurdock@gnu.ai.mit.edu>.
#
#       Also based on init script mountnfs.sh from initscripts package.
#
#       Modified for aoetools by David Martínez Moreno <ender@debian.org>.
#       Copyright 2006-2014.  Under GPLv2.
#
#       Support for LVM and other mount points contributed by Glen W. Mabey.
#       Support for RAID contributed by Gabor Kiss.
#
### BEGIN INIT INFO
# Provides:          aoe aoetools
# Required-Start:    $local_fs $network
# Required-Stop:     $local_fs $network
# Should-Start:
# Default-Start:     S
# Default-Stop:      0 6
# Short-Description: Begin AoE discovery and mount related filesystems.
# Description:       Begin AoE discovery and mount filesystems residing
#                    on AoE volumes.
### END INIT INFO

NAME=aoetools
DESC="AoE devices discovery and mounting AoE filesystems"

# shellcheck source=/dev/null
[ -f /etc/default/rcS ] && . /etc/default/rcS

. /lib/lsb/init-functions

# Include aoetools defaults if available
[ -f /etc/default/aoetools ] && . /etc/default/aoetools

set -e

mdadm="$(command -v mdadm || :)"
vgchange="$(command -v vgchange || :)"

create_fs_list() {
    # We start with a list from /etc/default/aoetools.
    waitaoe="$AOEMOUNTS"

    [ -f /etc/fstab ] || return
    #
    # Read through fstab line by line. If it contains /dev/etherd, set the flag
    # for mounting file systems over AoE.
    #

    exec 9<&0 </etc/fstab

    # shellcheck disable=SC2034 # fstype is indeed not used
    while read -r device mountpoint fstype fsopts rest; do
        case "$fsopts" in
            noauto | *,noauto | noauto,* | *,noauto,*)
                continue
                ;;
        esac
        case "$device" in
            '' | \#*)
                continue
                ;;
            /dev/etherd/*)
                waitaoe="$waitaoe $mountpoint"
                ;;
        esac
    done

    exec 0<&9 9<&-
}

do_start() {
    # We exit if the user does not want us to try this.
    if [ "$INTERFACES" = "none" ]; then
        log_action_msg "INTERFACES='none' in /etc/default/aoetools, not started."
        exit 0
    fi

    # Usually aoe is a module, so we will try to load it.
    if [ -n "$INTERFACES" ]; then
        modprobe aoe aoe_iflist="$INTERFACES" >/dev/null 2>&1 || true
    else
        modprobe aoe >/dev/null 2>&1 || true
    fi

    # Also, if udev is being used, the /dev/etherd devices
    # are not created until aoe module insertion, so...
    sleep 1 # ...we give udev a chance to populate /dev/etherd/.

    if [ ! -c /dev/etherd/discover ]; then
        log_failure_msg "Missing devices under /dev/etherd/.  Please run  aoe-mkdevs /dev/etherd and try again." >&2
        exit 1
    fi

    # Try to set up interfaces for discovery, if any.
    if [ -n "$INTERFACES" ]; then
        # shellcheck disable=SC2086 # See warning in /etc/default/aoetools
        aoe-interfaces $INTERFACES
    fi

    aoe-discover

    create_fs_list

    if [ -n "$waitaoe" ]; then
        echo
    fi

    if [ "$mdadm" ] && [ -n "$RAID_ARRAYS" ]; then
        echo
        echo "/sbin/mdadm is not present. Please install mdadm package and try again." >&2
        echo "RAID_ARRAYS option is ignored." >&2
        RAID_ARRAYS=''
    fi

    if [ -n "$RAID_ARRAYS" ]; then
        echo "Assembling RAID arrays..."
        for md in $RAID_ARRAYS; do
            /sbin/mdadm --assemble "$md" --scan
        done
    fi

    if [ "$vgchange" ] && [ -n "$LVMGROUPS" ]; then
        echo
        echo "The LVM2 tools are not present.  Please install lvm2 package and try again." >&2
        echo "We will not honour LVMGROUPS." >&2
        LVMGROUPS=''
    fi

    if [ -n "$LVMGROUPS" ]; then
        echo "Assembling LVM2 groups..."
        for vg in $LVMGROUPS; do
            vgchange --available=y "$vg"
        done
    fi

    if [ -n "$waitaoe" ]; then
        for mountpt in $waitaoe; do
            echo "Mounting $mountpt..."
            mount "$mountpt"
            #log_action_begin_msg "Waiting for $mountpt."
        done
    else
        echo "Nothing to mount."
    fi
}

do_stop() {
    create_fs_list

    if [ -n "$waitaoe" ]; then
        for mountpt in $waitaoe; do
            if awk '{print $2}' </proc/mounts | grep -qFx "$mountpt"; then
                echo "Unmounting $mountpt..."
                umount "$mountpt"
            fi
        done
    fi

    if [ -n "$LVMGROUPS" ]; then
        for vg in $LVMGROUPS; do
            vgchange --available=n "$vg"
        done
    fi

    if [ "$mdadm" ] && [ -n "$RAID_ARRAYS" ]; then
        echo "Stopping RAID arrays..."
        for md in $RAID_ARRAYS; do
            /sbin/mdadm --stop "/dev/$md"
        done
    fi

    # Removing the module prevents LVM's "Shutting down LVM Volume Groups..."
    # from hanging when an LVM has been setup on a device in /dev/etherd/.
    modprobe --remove aoe >/dev/null 2>&1 || true
}

do_status() {
    local aoe_mounts

    if lsmod | grep -qFx 'aoe'; then
        echo 'The aoe module is loaded.'
    fi
    # FIXME: Make something smarter like detect udev or a monolithic kernel.

    aoe_mounts="$(grep '/dev/etherd/' /proc/mounts || true)"
    if [ -n "$aoe_mounts" ]; then
        echo 'The following AoE file systems are mounted:'
        echo "$aoe_mounts" | awk '{print $2}'
    else
        echo 'No AoE file systems mounted.'
    fi
}

case "$1" in
    start | restart | reload | force-reload)
        printf '%s' "Starting $DESC: "
        do_start
        ;;
    stop)
        echo "Stopping $DESC: "
        do_stop
        ;;
    status)
        do_status
        ;;
    *)
        N=/etc/init.d/$NAME
        echo "Usage: $N {start|stop|restart|reload|force-reload|status}" >&2
        exit 1
        ;;
esac

exit 0