kiwix-serve helper for cybook

kiwix-serve-helper.sh

#!/bin/sh

###
# kiwix-serve helper for Cybook Odyssey
#
# launch upon mount/unmount event of the SD card and at boot time.
# - tries to kill a runnning kiwix-serve
# - tries to launch kiwix-serve if a library file is present
#
###

INTERNAL_STORAGE_MNT=/var/books
EXTERNAL_STORAGE_MNT=/mnt/sd/
KIWIX_SERVE=/usr/local/bin/kiwix-serve
KIWIX_PID=/var/run/kiwix-serve.pid
KIWIX_PORT=4242
KIWIX_LIBRARY=""
KIWIX_VERBOSE=1
binecho=/bin/echo
LIBRARY_FILE="data/library/library.xml"

usage () {
    echo "Usage: $0 start|restart|stop"
    echo ""
    echo "\tstart,"
    echo "\trestart:\tAt boot, mount or unmount"
    echo "\t\t\ttries to find a running kiwix-serve and kill it"
    echo "\t\t\ttries to find a library and launch kiwix-serve"
    echo ""
    echo "\tstop:\t\tAt system shutdown."
    echo "\t\t\ttries to find a running kiwix-serve and kill it"
}

launch_kiwix_serve() {
    if [ "$KIWIX_LIBRARY" = "" ];
    then
        return 0
    fi

    # verbose mode switch
    if [ $KIWIX_VERBOSE -eq 1 ];
    then
        verbose="--verbose"
    else
        verbose=""
    fi

    # launch kiwix-serve
    ${KIWIX_SERVE} --library -p ${KIWIX_PORT} ${verbose} ${KIWIX_LIBRARY} &
    kpid=$!
    ${binecho} $kpid > ${KIWIX_PID}

    ${binecho} "kiwix-serve PID: $kpid. Library: ${KIWIX_LIBRARY}"
    return $kpid
}

launch_if_library_exist() {
    ${binecho} -n "Attempt to launch kiwix-serve if library exist..."
    # look for library on SD card
    if [ -f "${EXTERNAL_STORAGE_MNT}/${LIBRARY_FILE}" ]; then
        KIWIX_LIBRARY="${EXTERNAL_STORAGE_MNT}/${LIBRARY_FILE}"
        ${binecho} "found on SD."
        launch_kiwix_serve
        return 1
    else
        ${binecho} -n "not on SD... Internal ? "
    fi

    # look for library on device (only if SD failed)
    if [ "$KIWIX_LIBRARY" = "" -a -f "${INTERNAL_STORAGE_MNT}/${LIBRARY_FILE}" ]; then
        KIWIX_LIBRARY="${INTERNAL_STORAGE_MNT}/${LIBRARY_FILE}"
        ${binecho} "found on device."
        launch_kiwix_serve
        return 1
    # no library found, return
    else
        ${binecho} "nope."
        return 0
    fi
}

kill_kiwix_if_running() {
    ${binecho} -n "Attempt to kill kiwix-serve if running..."
    if [ -f "${KIWIX_PID}" ];
    then
        kill -HUP `cat ${KIWIX_PID}`
        rm -f ${KIWIX_PID}
        ${binecho} "OK"
    else
        ${binecho} "nope."
    fi
}

# upon SD card mount (inserted, boot) or unmount
if [ "$1" = "start" -o "$1" = "restart" ]; then
    ${binecho} "launching/relaunching kiwix-serve."

    kill_kiwix_if_running

    launch_if_library_exist


# tear down on system shut down
elif [ "$1" = "stop" ]; then
    ${binecho} "shutting down kiwix-serve"

    kill_kiwix_if_running

# if first param neither `start` nor `stop`, exit.
else
    usage
    exit
fi