# vim: set ft=sh:

# larch1 -  live 'hook' for mkinitcpio: set up tmpfs and find boot device

# Author: Michael Towers (gradgrind) <mt.42@web.de>
#
# This file is part of the larch project.
#
#    larch is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#
#    larch is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with larch; if not, write to the Free Software Foundation, Inc.,
#    51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#
#----------------------------------------------------------------------------
#2008.02.11

# Replacement for msg which includes leading and trailing spaces
msg_ () { [ "${quiet}" != "y" ] && echo "$@"; }

# Try to mount a disk, partition or cdrom and look for the file
# 'larchboot' in the /larch directory.
# If LiveCD system found in the device, return 0, else return 1
# and leave the device mounted.
# $1 = device name (e.g. "/dev/hda2")
# $2 = directory where devices will be mounted
#
test_live_data_dir ()
{
    /bin/mount -r -t iso9660 "$1" $2 >/dev/null 2>/dev/null || \
    /bin/mount -r -t vfat -o noatime,nodiratime "$1" $2 >/dev/null 2>/dev/null || \
    /bin/mount -r -t ext2 -o noatime,nodiratime "$1" $2 >/dev/null 2>/dev/null
    if [ $? -eq 0 ]; then
        if [ -f "$2/larch/larchboot" ]; then
            LDEV="$1"
            msg_ " ... found at $1"
            return 0
        else
            /bin/umount $2 2>/dev/null
            msg_ " ... $1 mounted, but no 'larch/larchboot' found"
        fi
    else
        msg_ "  ... not $1"
    fi
    return 1
}

run_hook ()
{
    msg_ ":: Creating writeable filesystem (tmpfs)"
    /bin/mkdir "/tfs"
    # Boot option copy-to-ram (c2r)
    if [ "${c2r}" = "y" ]; then
        TFSSIZE="90%"
    else
        TFSSIZE="60%"
    fi
    /bin/mount -t tmpfs -o "size=${TFSSIZE}" tmpfs "/tfs"

    # Directory for test mounts (and then for live CD)
    cdmount="/livecd"
    /bin/mkdir "${cdmount}"

    # look for livecd data directory, first try ${root}
    LDEV="${root}"
    if [ "x${LDEV}" != "x" ]; then
        /bin/mount -r -t iso9660 "${LDEV}" "${cdmount}" >/dev/null 2>/dev/null || \
        /bin/mount -r -t vfat -o noatime,nodiratime "${LDEV}" "${cdmount}" >/dev/null 2>/dev/null || \
        /bin/mount -r -t ext2 -o noatime,nodiratime "${LDEV}" "${cdmount}" >/dev/null 2>/dev/null
        if [ $? -eq 0 ]; then
            if [ -d "${cdmount}/larch" ]; then
                msg_ ":: larch system at ${LDEV}"
            else
                /bin/umount "${cdmount}" 2>/dev/null
                echo "!! No larch system at ${LDEV}"
                LDEV=""
            fi
        else
            echo "!! Couldn't mount ${LDEV}"
            LDEV=""
        fi
    fi

    # then try cdroms
    if [ "x${LDEV}" = "x" ]; then
        msg_ ":: Looking for boot device"
        cdroms=$( /bin/cat /proc/sys/dev/cdrom/info | { while read a b c; do
                if [ "${a}" = "drive" -a "${b}" = "name:" ]; then
                    echo "${c}"
                    break
                fi
            done
        } )
        for i in ${cdroms}; do
            test_live_data_dir "/dev/${i}" "${cdmount}"
            if [ $? -eq 0 ]; then break; fi
        done
    fi

    # test USB devices (and disks) repeatedly until timed out
    if [ "x${LDEV}" = "x" ]; then
        msg_ ":: Searching for usb (and disk) devices .."
        for i in 1 2 3 4 5; do
            msg_ " :wait ${i} :::"
            /bin/sleep ${i}
            for d in /dev/sd[a-z][0-9]*; do
                test_live_data_dir "${d}" "${cdmount}"
                if [ $? -eq 0 ]; then break 2; fi
            done
            msg_ ":: Searching for usb cdroms .."
            for d in /dev/sr[0-9]*; do
                test_live_data_dir "${d}" "${cdmount}"
                if [ $? -eq 0 ]; then break 2; fi
            done
        done
    fi
}