package org.jscsi.target.connection.stage.fullfeature;
   
   
   import java.io.IOException;
   import java.security.DigestException;
   
   import org.jscsi.exception.InternetSCSIException;
   import org.jscsi.parser.BasicHeaderSegment;
   import org.jscsi.parser.ProtocolDataUnit;
  import org.jscsi.parser.scsi.SCSICommandParser;
  import org.jscsi.parser.scsi.SCSIResponseParser;
  import org.jscsi.parser.scsi.SCSIStatus;
  import org.jscsi.target.connection.TargetPduFactory;
  import org.jscsi.target.connection.phase.TargetFullFeaturePhase;
  import org.jscsi.target.scsi.ScsiResponseDataSegment;
  import org.jscsi.target.scsi.cdb.SendDiagnosticCdb;
  import org.jscsi.target.scsi.sense.senseDataDescriptor.senseKeySpecific.FieldPointerSenseKeySpecificData;
  import org.jscsi.target.settings.SettingsException;
  
  
  /**
   * A stage for processing <code>SEND DIAGNOSTIC</code> SCSI commands.
   * <p>
   * Only support for the default self-test feature, as required by SPC-3, is implemented. Request for other types of
   * self-test operations will be declined.
   * 
   * @author Andreas Ergenzinger
   */
  public class SendDiagnosticStage extends TargetFullFeatureStage {
  
      public SendDiagnosticStage (TargetFullFeaturePhase targetFullFeaturePhase) {
          super(targetFullFeaturePhase);
      }
  
      @Override
      public void execute (ProtocolDataUnit pdu) throws IOException , InterruptedException , InternetSCSIException , DigestException , SettingsException {
  
          final BasicHeaderSegment bhs = pdu.getBasicHeaderSegment();
          final SCSICommandParser parser = (SCSICommandParser) bhs.getParser();
  
          ProtocolDataUnit responsePdu = null;// the response PDU
  
          // get command details in CDB
          final SendDiagnosticCdb cdb = new SendDiagnosticCdb(parser.getCDB());
          final FieldPointerSenseKeySpecificData[] illegalFieldPointers = cdb.getIllegalFieldPointers();
  
          if (illegalFieldPointers != null) {
              // an illegal request has been made
  
              responsePdu = createFixedFormatErrorPdu(illegalFieldPointers,// senseKeySpecificData
                      bhs.getInitiatorTaskTag(),// initiatorTaskTag
                      parser.getExpectedDataTransferLength());// expectedDataTransferLength
  
          } else {
              // PDU is okay
              // carry out command
  
              /*
               * The self-test bit is 1, since request of a non-default self-test is not supported and would have led to
               * illegalFieldPointer != null A self-test (SELFTEST) bit set to one specifies that the device server shall
               * perform the logical unit default self-test. If the self-test successfully passes, the command shall be
               * terminated with GOOD status. If the self-test fails, the command shall be terminated with CHECK CONDITION
               * status, with the sense key set to HARDWARE ERROR. The self-test is always successful.
               */
              responsePdu = TargetPduFactory.createSCSIResponsePdu(false,// bidirectionalReadResidualOverflow
                      false,// bidirectionalReadResidualUnderflow
                      false,// residualOverflow
                      false,// residualUnderflow,
                      SCSIResponseParser.ServiceResponse.COMMAND_COMPLETED_AT_TARGET,// response,
                      SCSIStatus.GOOD,// status,
                      bhs.getInitiatorTaskTag(),// initiatorTaskTag,
                      0,// snackTag
                      0,// expectedDataSequenceNumber
                      0,// bidirectionalReadResidualCount
                      0,// residualCount
                      ScsiResponseDataSegment.EMPTY_DATA_SEGMENT);// data
                                                                  // segment
          }
  
          // send response
          connection.sendPdu(responsePdu);
      }
  
  }