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);

     }

 }