core/larch-live/lib/initcpio/hooks/larch1

# 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
#
#----------------------------------------------------------------------------
#2010.02.15

# Replacement for msg which includes leading and trailing spaces
msg_ () { [ "${quiet}" != "y" ] && echo "$@"; }
# Version which requires 'verbose' flag to output
msg_v () { [ "${quiet}" != "y" ] && [ "${verbose}" = "y" ] && echo "$@"; }

testdevice ()
{
    fstype=$( blkid -s TYPE -o value ${LDEV} )
    /bin/mount -r -t ${fstype} -o noatime "${LDEV}" "${cdmount}" >/dev/null 2>/dev/null
    if [ $? -eq 0 ]; then
        if [ -f "${cdmount}/larch/system.sqf" ]; then
            msg ":: larch system at ${LDEV}"
        else
            /bin/umount "${cdmount}" 2>/dev/null
            msg_v  "!! No larch system at ${LDEV}"
            LDEV=""
        fi
    else
        msg_v "!! Couldn't mount ${LDEV}"
        LDEV=""
    fi
}

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

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

    modprobe loop

    # Loop device test every second up to some limit
    if [ "x${usbdelay}" != "x" ]; then
        waittime=${usbdelay}
    else
        waittime=12
    fi
    waitcount=0
    while [ ${waittime} -ne ${waitcount} ]; do

        if [ "x${uuid}" != "x" ]; then
            [ ${waitcount} -eq 0 ] && msg ":: Looking for UUID ${uuid}"
            LDEV=$( blkid -U ${uuid} )
            if [ "x${LDEV}" != "x" ]; then
                testdevice
            fi

        elif [ "x${label}" != "x" ]; then
            [ ${waitcount} -eq 0 ] && msg ":: Looking for LABEL ${label}"
            LDEV=$( blkid -L ${label} )
            if [ "x${LDEV}" != "x" ]; then
                testdevice
            fi

        elif [ "x${root}" != "x" ]; then
            [ ${waitcount} -eq 0 ] && msg ": Looking for ${root}"
            # Set LDEV directly, e.g. /dev/sda1
            if [ -e ${root} ]; then
                LDEV=${root}
                testdevice
            fi

        else
            [ ${waitcount} -eq 0 ] && msg ":: Looking for boot device"
            if [ "x${nocd}" = "x" ]; then
                # Look for CD
                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 ${cdroms}; do
                    LDEV=/dev/${i}
                    testdevice
                    if [ "x${LDEV}" != "x" ]; then
                        break
                    fi
                done
            fi

            # Test partitions
            if [ "x${LDEV}" = "x" ]; then
                for d in /dev/sd[a-z][0-9]*; do
                    LDEV=${d}
                    testdevice
                    if [ "x${LDEV}" != "x" ]; then
                        if [ -f "${cdmount}/larch/larchboot" ]; then
                            break
                        else
                            msg ":: ${LDEV} has no /larch/larchboot file"
                            LDEV=""
                        fi
                    fi
                done
            fi

        fi

        [ "x${LDEV}" != "x" ] && break

        /bin/sleep 1
        waitcount=$(( ${waitcount} + 1 ))
    done

    if [ "x${LDEV}" = "x" ]; then
        echo "!! Sorry, couldn't find boot medium ..."
        echo "!! If the larch system is on a partition you should specify"
        echo "!! its UUID with 'uuid=xxxxxxx' or its LABEL with 'label=xxxxxx'"
        echo "!! as a boot parameter. 'root=/dev/sdXY' is another possibility."
        break="y"
    fi
}