use Win32;
use strict;
use Win32::OLE qw( in );
use Win32::Daemon;
use Win32::API::Prototype;

# Declare api
ApiLink( 'kernel32.dll', 'BOOL DeleteVolumeMountPoint( LPCTSTR lpszVolumeMountPoint )' ) || die;
ApiLink( 'kernel32.dll', 'BOOL SetVolumeMountPoint( LPCTSTR lpszVolumeMountPoint, LPCTSTR lpszVolumeName ) ' ) || die;
ApiLink( 'kernel32.dll', 'BOOL GetVolumeNameForVolumeMountPoint(  LPCTSTR lpszVolumeMountPoint,  LPTSTR lpszVolumeName,  DWORD cchBufferLength )' ) || die;

my ($State);
my $SERVICE_SLEEP_TIME = 20; # 20 milliseconds
my $PrevState          = SERVICE_START_PENDING;

# Start one loop to manage the services
while( SERVICE_STOPPED != ( $State = Win32::Daemon::State() ) )
{
    if( SERVICE_START_PENDING == $State )
    {
        # Initialization code
        Win32::Daemon::State( SERVICE_RUNNING );
        $PrevState = SERVICE_RUNNING;
    }
    elsif( SERVICE_STOP_PENDING == $State )
    {
        Win32::Daemon::State( SERVICE_STOPPED );
    }
    elsif( SERVICE_PAUSE_PENDING == $State )
    {
        # "Pausing...";
        Win32::Daemon::State( SERVICE_PAUSED );
        $PrevState = SERVICE_PAUSED;
        next;
    }
    elsif( SERVICE_CONTINUE_PENDING == $State )
    {
      # "Resuming...";
      Win32::Daemon::State( SERVICE_RUNNING );
      $PrevState = SERVICE_RUNNING;
      next;
    }
    elsif( SERVICE_STOP_PENDING == $State )
    {
      # "Stopping...";
      Win32::Daemon::State( SERVICE_STOPPED );
      $PrevState = SERVICE_STOPPED;
      next;
    }
    elsif( SERVICE_RUNNING == $State )
    {
        my $VolumeMountPoint = GetLogicalDisk();
        # if the drive is not U:, change
        if ( $VolumeMountPoint ne "U:" )
        {
            my $VolumeName = NewString( 256 );
            if (! GetVolumeNameForVolumeMountPoint ("$VolumeMountPoint\\", $VolumeName, 256) )
            {
                print Win32::GetLastError();
            }
            else
            {
                $VolumeName =~ /(\x00)/; $VolumeName = $`;  # Remove null
            }

            if (! DeleteVolumeMountPoint("$VolumeMountPoint\\") )
            {
                print Win32::GetLastError();
            }

            if (! SetVolumeMountPoint ("U:\\", $VolumeName ))
            {
                print Win32::GetLastError();
            }
        }        
    }
    else
    {
      # Got an unhandled control message. Set the state to
      # whatever the previous state was.
      Win32::Daemon::State( $PrevState );
    }        # Check for any outstanding commands. Pass in a non zero value
        # and it resets the Last Message to SERVICE_CONTROL_NONE.
        if( SERVICE_CONTROL_NONE != ( my $Message = Win32::Daemon::QueryLastMessage( 1 ) ) )
        {
          if( SERVICE_CONTROL_INTERROGATE == $Message )
          {
            # Got here if the Service Control Manager is requesting
            # the current state of the service. This can happen for
            # a variety of reasons. Report the last state we set.
            Win32::Daemon::State( $PrevState );
          }
        elsif( SERVICE_CONTROL_SHUTDOWN == $Message )
        {
          # Yikes! The system is shutting down. We had better clean up
          # and stop.
          # Tell the SCM that we are preparing to shutdown and that we expect
          # it to take 25 seconds (so don't terminate us for at least 25 seconds)...
          Win32::Daemon::State( SERVICE_STOP_PENDING, 25000 );
        }
      }
      # Snooze for awhile so we don't suck up cpu time...
      Win32::Sleep( $SERVICE_SLEEP_TIME );
   }
   # We are done so close down...
   Win32::Daemon::StopService();


sub GetLogicalDisk
{
# Here, you could do a query to verify if the USB driver in on Windows,
# look at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmisdk/wmi/win32_logicaldisk.asp
# site to verify wich value you could use, like serialnumber or volume name

    my $WMIServices = Win32::OLE->GetObject ( "winmgmts:{impersonationLevel=impersonate, (security)}//./root/cimv2" ) || die;
    my $DriveCollection = $WMIServices->ExecQuery ( 'select * from Win32_LogicalDisk where VolumeSerialNumber = "2CBE1114"' ) || die "Query Failed";

    foreach my $Drive ( in( $DriveCollection ) )
    {
        return $Drive->{'Name'};
    }
}