Asus Router - Move Syslog to USB

#!/bin/sh

#===============================================================================
#
# Moves syslog between internal flash memory and USB drive or scans a log for BOOT errors and custom action messages.
#
#          Called as the last line of init-start preferably after 180sec sleep delay!!!!
#                 and as last line of services-stop
#
#   Jan 2017 http://pastebin.com/embed_js/M0qUATyj
#
#
#   e.g.   syslog-move.sh   [help|-h|status| file_name | reset ]
#
#
#          syslog-move.sh
#                            If '/tmp/BOOTINPROGRESS' exists, moves syslog to USB '/tmp/mnt/$MOUNTED/Syslog/syslog.log'
#          syslog-move.sh    reset
#                            Moves syslog back to '/tmp/syslog.log' (flash memory)
#          syslog-move.sh    /tmp/mnt/$MOUNTED/Syslog/syslog.log-20170125-153049-BOOT.txt
#                            Scans file for 'abnormal messages and custom messages and creates 'BOOT_Errors.txt' & 'MyCustomActions.txt'
#          syslog-move.sh    help
#                            This help information

#   e.g. init-start
#
#       #!/bin/sh
#       /usr/bin/logger -s -t "($(basename $0))" $$ "Martineau $MYROUTER BOOT in progress... [$@]"
#       # NOTE: Can't use Flash drive /tmp/mnt/$MYROUTER/ 'cos it hasn't been mounted yet :-(
#       # 'flock' is probably a better solution rather than the 'echo' ;-)
#       HARDWARE_MODEL=$(nvram get productid)
#       MYROUTER=$(nvram get computer_name)
#       BUILDNO=$(nvram get buildno)
#       EXTENDNO=$(nvram get extendno)
#       echo $$"-"`date` > /tmp/BOOTINPROGRESS
#       rm /tmp/SHUTDOWNINPROGRESS
#       # Should be sufficient to cover physical BOOT process?
#       logger -st "($(basename $0))" $$ "Paused for 3 mins....."
#       sleep 180
#       # Call custom scripts/commands here e.g. cifs.sh / cru etc. here
#       /usr/bin/logger -st "($(basename $0))" $$ "Martineau" $MYROUTER "BOOT Completed Firmware build" $BUILDNO $EXTENDNO "[$@]"
#       # Move Syslog to USB Flash drive
#       /jffs/scripts/syslog-move.sh
#       rm /tmp/BOOTINPROGRESS
#
#   e.g. services-stop
#
#       #!/bin/sh
#       /usr/bin/logger -st "($(basename $0))" $$ "Martineau Services cleanup in progress... [$@]"
#       MYROUTER=$(nvram get computer_name)
#       # NOTE: Could use Flash drive /tmp/mnt/$MYROUTER/
#       # 'flock' is probably a better solution rather than the 'echo'
#       echo $$"-"`date` > /tmp/SHUTDOWNINPROGRESS                          # Will be deleted by init-start
#       /usr/bin/logger -st "($(basename $0))" $$ "Stopping rstats....."
#       service stop_rstats
#       /usr/bin/logger -st "($(basename $0))" $$ "Stopping cstats....."
#       service stop_cstats
#       # Call custom scripts/commands here e.g. Entware '/rc.unslung' etc. here
#       # At this point no further logger statements are recorded in Syslog?
#       #    so spoof a logger message!
#       echo `date "+%b   %d %T"` $MYROUTER "Spoof.logger (services-stop): Martineau Services shutdown cleanup complete."  >> /tmp/syslog.log
#       echo `date "+%b   %d %T"` $MYROUTER "Spoof.logger (services-stop): Saving syslog before Reboot..... "  >> /tmp/syslog.log
#       /usr/bin/logger -st "($(basename $0))" $$ "Saving Syslog before Reboot..... "
#       /jffs/scripts/syslog-move.sh
#       exit 0
#
GetLocationSTATUS () {
    # Identify media for current disposition of dataset i.e. is /tmp/syslog.log a link to USB?
    local ORG="?"
    if [[ -L "$SOURCE" ]];then
        #DEST="RAM"
        local WHERE="USB"
        local TEXT="is on"
    else
        #DEST="USB"
        local WHERE="RAM"
        local TEXT="is in"
    fi
    if [ -z $1 ];then
        logger -st "($(basename $0))" $$ $MYROUTER "Syslog '"$SOURCE"'" $TEXT $WHERE
    fi
    echo $WHERE
}
# Print between line beginning with'#==' to first blank line inclusive
ShowHelp() {
    awk '/^#==/{f=1} f{print; if (!NF) exit}' $0
}

# Help required?
if [ "$1" = "-h" ] || [ "$1" = "help" ]; then
   ShowHelp                                 # Show help
   exit 0
fi

SDx="sda1"                                          # Default - Change for sdb1 etc.

DEV_MOUNT=`df | grep -F "$SDx" | awk '{print $6}'`
if [ -z $DEV_MOUNT ];then
    logger -st "($(basename $0))" $$ "***ERROR '/dev/"$SDx"' mount point not found!"
    echo -e "\a"
    exit 99
fi

SOURCE="/tmp/syslog.log"                            # Original source of the syslog in Router flash memory
SYSLOG=$DEV_MOUNT"/Syslog/syslog.log"               # Destination of the syslog on USB disk
ORIGINAL=$(GetLocationSTATUS)                       # Current physical location of syslog.log
DEST="USB"                                          # Default target destination

ERRORFILE=$DEV_MOUNT"/Syslog/BOOT_Errors.txt"               # Results of scanning log for 'abnormal' messages
MYCUSTOMFILE=$DEV_MOUNT"/Syslog/MyCustomActions.txt"        # Results of scanning log for 'custom action' events

# Here because we need the global variables set!
if [ "$1" == "status" ];then
    echo " "
    ORIGINAL=$(GetLocationSTATUS "?")
    # Confirm
    ls -l $SOURCE
    exit 0
fi

logger -st "($(basename $0))" $$ "Syslog Housekeeping starting....." [$@]

NOW=$(date +"%Y%m%d-%H%M%S")    # current date and time

# Explicit request to revert back to flash memory (as used in services-stop @ REBOOT shutdown)
if [ "$1" == "reset" ];then
    DEST="RAM"
fi

if [ -z $1 ] || [ "$1" == "reset" ] ; then

    # True REBOOT in progress? see init-start
    if [ -e /tmp/BOOTINPROGRESS  ]; then
        logger -st "($(basename $0))" $$ "Boot-in-Progress '/tmp/BOOTINPROGRESS' detected."
        if [ -f $SYSLOG ];then
            logger -st "($(basename $0))" $$ "Renaming previous USB '"$SYSLOG"' to '"$SYSLOG-$NOW"'"
            mv $SYSLOG $SYSLOG-${NOW}_shutdown.txt          # Rename previous USB syslog
        fi
        logger -st "($(basename $0))" $$ "Creating '"$SYSLOG-$NOW-BOOT.raw"'"
        killall syslogd
        sleep 1
        cp $SOURCE $SYSLOG-$NOW-BOOT.raw        # copy current physical /tmp syslog to the new location
        rm $SOURCE
        # Remove all duplicated 'shutdown' lines - they are always incomplete anyway?
        logger -st "($(basename $0))" $$ "Editing '"$SYSLOG-$NOW-BOOT.raw"' -> '"$SYSLOG-$NOW-BOOT.txt"'"
        RC=$(sed -n '/^Aug/,$p' $SYSLOG-$NOW"-BOOT.raw" > $SYSLOG-$NOW"-BOOT.txt")  # i.e. upto 'Aug  1 01:00:15 syslogd started: BusyBox v1.25.1'
        rm $SYSLOG-$NOW-BOOT.raw
        SCANTHIS=$SYSLOG-$NOW-BOOT.txt
    else
        logger -st "($(basename $0))" $$ "Creating '"$SYSLOG-$NOW.txt"'"
        #killall syslogd
        sleep 1
        cp $SOURCE $SYSLOG-$NOW.txt             # copy current /tmp/syslog.log to the new location
        rm $SOURCE
        SCANTHIS=$SYSLOG-$NOW.txt
    fi

    killall syslogd

    # Start SYSLOG on the USB disk with infinite size i.e. no GDG creation if no ARG supplied
    if [ "$DEST" == "USB" ];then
        if [ "$ORIGINAL" == "RAM" ];then
            ACTION="moved to"
        else
            ACTION="retained on"
        fi
        logger -st "($(basename $0))" $$ "Syslog" $ACTION "USB drive '"$SYSLOG"'"
        CMD="syslogd -O $SYSLOG -s 0"
        $CMD
    else
        logger -st "($(basename $0))" $$ "Syslog reset to internal flash memory '"$SOURCE"'"   # display OK message
        CMD="syslogd -O $SOURCE"
        $CMD                    # Put it back where ASUS expect its to be ? /tmp/syslog.log in internal memory
    fi

    if [ "$?" -ne 0 ]; then    # check for error
        logger -st "($(basename $0))" $$ "***ERROR rc=" $? "'"$CMD"'"
        exit $?
    fi

    if [ "$DEST" == "USB" ];then
        # Allow Router GUI to see the Syslog!!!!! otherwise it shows it empty!!!
        rm $SOURCE 2> /dev/null
        CMD="ln -s $SYSLOG $SOURCE"
        $CMD          # create a symbolic link from the original syslog to the USB one

        if [ "$?" -ne 0 ]; then
            logger -st "($(basename $0))" $$ "**ERROR rc=" $? "'"$CMD"'"
            echo -e "\a"
        fi
    fi

    # Confirm????
    #ls -l $SOURCE

else
    SCANTHIS=$DEV_MOUNT"/Syslog/$1"                         # Scan filename provided
fi


#if [ -e /tmp/BOOTINPROGRESS  ]; then
    # Scan the BOOT log for errors i.e. literal 'ERROR' or 'FAILED' or 'ABORT' case insensitive
    logger -st "($(basename $0))" $$ "SYSLOG 'abnormal' message scanning: '" $SCANTHIS"'"
    echo "Scanning '"$SCANTHIS"'" > $ERRORFILE
    ERROR_LINE_CNT=`grep -c -E -i "ERROR|FAILED|ABORT" $SCANTHIS`
    #logger -st "($(basename $0))" $$ "**DEBUG ERROR_LINE_CNT="$ERROR_LINE_CNT
    if [ "$ERROR_LINE_CNT" -gt 0 ]; then
        echo -e "\a"
        logger -st "($(basename $0))" $$ "Scan of '"$SCANTHIS"' found" $ERROR_LINE_CNT "errors"
        RC=`grep -iE "ERROR|FAILED|ABORT" $SCANTHIS >> $ERRORFILE`
        echo
    else
        echo "Nothing 'abnormal' - ERROR or FAILED or ABORT found." >> $ERRORFILE
    fi
    # Scan the log for my custom script actions...
    logger -st "($(basename $0))" $$ "SYSLOG 'custom action' message scanning: '"$SCANTHIS"'"
    CUSTOM_LINE_CNT=`grep -E "\):" $SCANTHIS | grep -vE "]:|kernel:"  > $MYCUSTOMFILE`
#fi

logger -st "($(basename $0))" $$ "Syslog Housekeeping complete for '"$SCANTHIS"'"

exit 0