upgrade_check.sh in Tolino Shine

#!/system/bin/b    ash -x
i=0
rm /data/no_sd_upgrade

upgrade_check(){
sleep 6
if [ -e /mnt/sdcard/extsd/update.zip ] ; then
        echo "---> recovery mode setting ---------------------------------------"
        rm /cache/downloadfile*
        sync
        sync
        if [ -e /mnt/sdcard/extsd/update_mark ] ; then
#                mv /mnt/sdcard/extsd/update.zip /mnt/sdcard/extsd/update.zip_old
                rm /mnt/sdcard/extsd/update.zip
                rm /mnt/sdcard/extsd/update_mark
                upgrade_check
#        else
#                mkdir /cache/recovery
#                echo '--update_package=/sdcard/update.zip' > /cache/recovery/command
#                am start -n com.ntx.msg/.MsgUpgradeActivity
#                sync
#                sync
#                sleep 10
#                sync
#                sync
#                reboot
        fi
elif [ -e /mnt/sdcard/extsd/waveform.bin ]; then
        echo "---> Programming waveform ----------------------------------------"
        busybox dd if=/mnt/sdcard/extsd/waveform.bin of=/dev/mmcblk0 bs=512 seek=14336
        sync
        sync
        mv /mnt/sdcard/extsd/waveform.bin /mnt/sdcard/extsd/waveform.bin_old
        sync
        sync
        am start -n com.ntx.msg/.MsgWaveformActivity
        sync
        sync
# xiaobo begin of adb_open
# elif [ -e /mnt/sdcard/extsd/adb_open ]; then
#        setprop persist.service.adb.enable 1
#        sync
#        sync
# elif [ -e /mnt/sdcard/extsd/adb_close ]; then
#        setprop persist.service.adb.enable 0
#        sync
#        sync
# xiaobo end of adb open
elif [ -e /mnt/sdcard/extsd/recovery.img ] || [ -e /cache/upgrade/recovery.img ]; then
        echo "---> Programming partition RECOVERY ----------------------------------"
        busybox dd if=/mnt/sdcard/extsd/recovery.img of=/dev/block/mmcblk0p4 bs=8M
        busybox dd if=/cache/upgrade/recovery.img of=/dev/block/mmcblk0p4 bs=8M
        sync
        sync
        e2fsck -dy /dev/block/mmcblk0p4
        sync
        sync
        mv /mnt/sdcard/extsd/recovery.img /mnt/sdcard/extsd/recovery.img_old
        rm /cache/upgrade/recovery.img
        sync
        sync
        am start -a android.intent.action.ACTION_REQUEST_SHUTDOWN
elif [ -e /mnt/sdcard/show_info ] || [ -e /mnt/sdcard/extsd/show_info ]; then
        echo "---> Programming show info. ----------------------------------"
        sync
        sync
        am start -n com.ntx.msg/.MsgShowInfoActivity
        sync
        sync
else
        if [ "$i" -le 5 ]; then
            i=$((i + 1))
            upgrade_check
        else
            busybox touch /data/no_sd_upgrade
        fi
fi
}

upgrade_check