package org.jscsi.target.connection.stage.fullfeature;

 import org.jscsi.target.connection.phase.TargetFullFeaturePhase;

 import org.jscsi.target.scsi.cdb.CommandDescriptorBlock;

 import org.jscsi.target.scsi.cdb.ReadOrWriteCdb;

 import org.jscsi.target.scsi.sense.senseDataDescriptor.senseKeySpecific.FieldPointerSenseKeySpecificData;

 /**

  * This is an abstract superclass for stages that handle PDUs with command descriptor blocks of the

  * {@link ReadOrWriteCdb} class.

  * 

  * @author Andreas Ergenzinger

  */

 public abstract class ReadOrWriteStage extends TargetFullFeatureStage {

     public ReadOrWriteStage (TargetFullFeaturePhase targetFullFeaturePhase) {

         super(targetFullFeaturePhase);

     }

     /**

      * Checks if the <code>LOGICAL BLOCK ADDRESS</code> and <code>TRANSFER

      * LENGTH</code> fields in the passed {@link ReadOrWriteCdb} are acceptable. If illegal values are detected, an

      * instance of {@link FieldPointerSenseKeySpecificData} describing the problem will be added to the

      * {@link ReadOrWriteCdb}'s queue-

      * 

      * @param cdb a read or write command descriptor block to check

      * @see CommandDescriptorBlock#getIllegalFieldPointers()

      */

     protected void checkOverAndUnderflow (final ReadOrWriteCdb cdb) {

         // check if requested blocks are out of bounds

         final int boundsCheck = session.getStorageModule().checkBounds(cdb.getLogicalBlockAddress(), cdb.getTransferLength());

         // add illegal field pointer, or not

         if (boundsCheck == 1)

             cdb.addIllegalFieldPointerForLogicalBlockAddress();

         else if (boundsCheck == 2) cdb.addIllegalFieldPointerForTransferLength();

     }

 }