#! /bin/sh
### BEGIN INIT INFO
# Provides:          casper
# Required-Start:    $syslog
# Required-Stop:
# Should-Start:      $local_fs
# Should-Stop:       halt reboot
# X-Stop-After:      umountroot
# Default-Start:
# Default-Stop:      0 6
# Short-Description: Casper init script
# Description:       Resyncs snapshots, evantually caches files in order
#                    to let remove the media.
### END INIT INFO

# Author: Tollef Fog Heen <tfheen@canonical.com>
#         Marco Amadori <marco.amadori@gmail.com>
#
PATH=/usr/sbin:/usr/bin:/sbin:/bin
NAME=casper
SCRIPTNAME=/etc/init.d/${NAME}
DO_SNAPSHOT=/sbin/${NAME}-snapshot

# Exit if system was not booted by casper
grep -qs boot=casper /proc/cmdline || exit 0

# Exit if the system was booted from an ISO image rather than a physical CD
grep -qs find_iso= /proc/cmdline && exit 0

# Read configuration variable file if it is present
[ -r /etc/$NAME.conf ] && . /etc/$NAME.conf

# Load the VERBOSE setting and other rcS variables
[ -f /etc/default/rcS ] && . /etc/default/rcS

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions

# Try to cache everything we're likely to need after ejecting.  This
# is fragile and simple-minded, but our options are limited.
cache_path() {
    path="$1"

    if [ -d "$path" ]; then
        find "$path" -type f | xargs cat > /dev/null 2>&1
    elif [ -f "$path" ]; then
        if [ -x "$path" ]; then
            if file -L "$path" | grep -q 'dynamically linked'; then
                for lib in $(ldd "$path" | awk '{ print $3 }'); do
                    cache_path "$lib"
                done
            fi
        fi
        cat "$path" >/dev/null 2>&1
    fi
}

do_stop ()
{
    if [ ! -z "${ROOTSNAP}" ]; then
        $DO_SNAPSHOT --resync-string="${ROOTSNAP}"
    fi

    if [ ! -z "${HOMESNAP}" ]; then
        $DO_SNAPSHOT --resync-string="${HOMESNAP}"
    fi

    # check for netboot
    if [ ! -z "${NETBOOT}" ] || grep -qs netboot /proc/cmdline || grep -qsi root=/dev/nfs /proc/cmdline  || grep -qsi root=/dev/cifs /proc/cmdline ; then
        return 0
    fi

    # Don't prompt to eject the SD card on Babbage board, where we reuse it
    # as a quasi-boot-floppy. Technically this uses a bit of ubiquity
    # (archdetect), but since this is mostly only relevant for
    # installations, who cares ...
    if type archdetect >/dev/null 2>&1; then
        subarch="$(archdetect)"
        case $subarch in
            arm*/imx51)
                return 0
                ;;
        esac
    fi

    prompt=1
    if grep -qs noprompt /proc/cmdline; then
        prompt=
    fi

    for path in $(which halt) $(which reboot) /etc/rc?.d /etc/default $(which stty) /bin/plymouth /sbin/usplash_write; do
        cache_path "$path"
    done

    device="$(grep " /cdrom " /proc/mounts | cut -d' ' -f1)" || device=
    # If /cdrom isn't mounted, don't try to eject it
    if [ -z "$device" ]; then
        return 0
    fi

    # If the device exists but can't be found in /sys/block, it's most likely a partition
    # so unmount it (lazy mode) and sync
    if [ -b "$device" ] && [ ! -f "/sys/block/$(basename $device)/removable" ]; then
        umount -l $device >/dev/null 2>&1
        sync
        return 0
    fi

    # If we're still there, then we're probably a cdrom or other media
    # ship the eject if the kernel says the media isn't removable
    if [ "$(cat /sys/block/$(basename $device)/removable)" = "0" ]; then
        return 0
    fi

    eject -p -m /cdrom >/dev/null 2>&1

    [ "$prompt" ] || return 0

    # XXX - i18n
    MSG="Please remove installation media and close the tray (if any) then press ENTER: "

    if [ -x /bin/plymouth ] && plymouth --ping; then
        plymouth message --text="$MSG"
        plymouth watch-keystroke > /dev/null
    else
        stty sane < /dev/console

        echo $MSG > /dev/console
        if [ -x /sbin/usplash_write ]; then
            /sbin/usplash_write "TIMEOUT 86400"
            /sbin/usplash_write "TEXT-URGENT Please remove installation media, close the tray"
            /sbin/usplash_write "TEXT-URGENT (if any) and press ENTER to continue"
        fi
        read x < /dev/console
    fi
}

case "$1" in
    restart|reload|force-reload|status)
        [ "$VERBOSE" != no ] && log_end_msg 0
        ;;
    # We normally run on start; stop is just for backwards compatibility.
    start|stop)
        log_begin_msg "${NAME} is resyncing snapshots and caching reboot files..."
        do_stop
        case "$?" in
            0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
            2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
        esac
        ;;
    *)
        log_success_msg "Usage: $SCRIPTNAME {start|stop|restart|force-reload}" >&2
        exit 3
        ;;
esac