Android Open Source - libaums Command Status Wrapper

• Back to Hardware/usb  ↑

From Project

Back to project page libaums.

License

The source code is released under:

Apache License

Java Source Code

/*
 * (C) Copyright 2014 mjahnen <jahnen@in.tum.de>
 */*w w  w .j ava  2s.c o m*/
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

package com.github.mjdev.libaums.driver.scsi.commands;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import android.util.Log;

/**
 * This class represents the command status wrapper (CSW) in the SCSI
 * transparent command set standard, which is transmitted from the device to the
 * host after the data phase (if any).
 * 
 * @author mjahnen
 * 
 */
public class CommandStatusWrapper {

  /**
   * SCSI command has successfully been executed.
   */
  public static final int COMMAND_PASSED = 0;
  /**
   * SCSI command could not be executed, host should issue an SCSI request
   * sense.
   * 
   * @see com.github.mjdev.libaums.driver.scsi.commands.ScsiRequestSense
   */
  public static final int COMMAND_FAILED = 1;
  /**
   * SCSI command could not be executed, host should issue a mass storage
   * reset.
   */
  public static final int PHASE_ERROR = 2;

  /**
   * Every CSW has the same size.
   */
  public static final int SIZE = 13;

  private static final String TAG = CommandStatusWrapper.class.getSimpleName();

  private static final int D_CSW_SIGNATURE = 0x53425355;

  private int dCswSignature;
  private int dCswTag;
  private int dCswDataResidue;
  private byte bCswStatus;

  /**
   * Constructs a command block wrapper from the specified buffer.
   * 
   * @param buffer
   *            The data where the command block wrapper is located.
   * @return A new command block wrapper.
   */
  public static CommandStatusWrapper read(ByteBuffer buffer) {
    buffer.order(ByteOrder.LITTLE_ENDIAN);

    CommandStatusWrapper csw = new CommandStatusWrapper();
    csw.dCswSignature = buffer.getInt();
    if (csw.dCswSignature != D_CSW_SIGNATURE) {
      Log.e(TAG, "unexpected dCSWSignature");
    }
    csw.dCswTag = buffer.getInt();
    csw.dCswDataResidue = buffer.getInt();
    csw.bCswStatus = buffer.get();
    return csw;
  }

  /**
   * Returns the tag which can be used to determine the corresponding
   * {@link com.github.mjdev.libaums.driver.scsi.commands.CommandBlockWrapper
   * CBW}.
   * 
   * @return The command status wrapper tag.
   * @see com.github.mjdev.libaums.driver.scsi.commands.CommandBlockWrapper
   *      #getdCswTag()
   */
  public int getdCswTag() {
    return dCswTag;
  }

  /**
   * Returns the amount of bytes which has not been processed yet in the data
   * phase.
   * 
   * @return The amount of bytes.
   */
  public int getdCswDataResidue() {
    return dCswDataResidue;
  }

  /**
   * Returns the status of execution of the transmitted SCSI command.
   * 
   * @return The status.
   * @see com.github.mjdev.libaums.driver.scsi.commands.CommandStatusWrapper
   *      #COMMAND_PASSED
   * @see com.github.mjdev.libaums.driver.scsi.commands.CommandStatusWrapper
   *      #COMMAND_FAILED
   * @see com.github.mjdev.libaums.driver.scsi.commands.CommandStatusWrapper
   *      #PHASE_ERROR
   */
  public byte getbCswStatus() {
    return bCswStatus;
  }
}

Java Source Code List

• Back to Hardware/usb  ↑