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/**
* Copyright (c) 2012, University of Konstanz, Distributed Systems Group All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation and/or other materials provided with the
* distribution. * Neither the name of the University of Konstanz nor the names of its contributors may be used to
* endorse or promote products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.jscsi.parser.scsi;
import java.nio.ByteBuffer;
/**
* SCSICommandDescriptorBlockParser
*
* This class generates a SCSI Command Descriptor Block.
*
* @author Volker Wildi
*/
public final class SCSICommandDescriptorBlockParser {
/**
* @author Volker Wildi
*/
// private static enum GroupCode {
// /** */
// SIX_BYTE_COMMAND((byte) 0x06),
// /** */
// TEN_BYTE_COMMAND((byte) 0x0A),
// /** */
// TWELVE_BYTE_COMMAND((byte) 0x0C),
// /** */
// SIXTEEN_BYTE_COMMAND((byte) 0x10),
// /** */
// VENDOR_SPECIFIC((byte) 0x00);
//
// private byte value;
//
// private static Map mapping;
//
// private GroupCode(final byte newValue) {
//
// if (GroupCode.mapping == null) {
// GroupCode.mapping = new HashMap();
// }
//
// GroupCode.mapping.put(newValue, this);
// value = newValue;
// }
//
// /**
// * Returns the value of this enumeration.
// *
// * @return The value of this enumeration.
// */
// public final byte value() {
//
// return value;
// }
//
// /**
// * Returns the constant defined for the given value.
// *
// * @param value
// * The value to search for.
// * @return The constant defined for the given value. Or
// * null, if this value is not defined by this
// * enumeration.
// */
// public static final GroupCode valueOf(final byte value) {
//
// return GroupCode.mapping.get(value);
// }
//
// }
//
// //
// --------------------------------------------------------------------------
// //
// --------------------------------------------------------------------------
/** The default or minimal length of a CDB is 16 bytes. */
private static final int DEFAULT_CDB_LENGTH = 16;
// private static final int STANDARD_BYTES = 2;
//
// private static final int GROUP_CODE_SHIFT = 5;
//
// private static final byte GROUP_CODE_MASK = (byte) 0xE0;
//
// private static final byte COMMAND_CODE_MASK = 0x1F;
//
// private static final byte NACA_FLAG_MASK = 0x04;
//
// private static final byte LINK_FLAG_MASK = 0x01;
//
// //
// --------------------------------------------------------------------------
// //
// --------------------------------------------------------------------------
//
// private byte opCode;
//
// private ByteBuffer specificParameters;
//
// private byte control;
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
private SCSICommandDescriptorBlockParser () {
super();
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
// public final int serialize(final ByteBuffer dst, final int offset) {
//
// dst.position(offset);
//
// if (dst.remaining() < getTotalLength()) {
// throw new IllegalArgumentException("Destination buffer is too small.");
// }
//
// dst.put(serializeOperationCodeByte());
//
// for (byte b = 0; b < getLength().value(); b++) {
// dst.put(serializeSpecificParameters());
// }
//
// dst.put(serializeControlByte());
//
// return dst.position() - offset;
// }
//
// public final int deserialize(final ByteBuffer src, final int offset) {
//
// src.position(offset);
//
// if (src.remaining() < DEFAULT_CDB_LENGTH) {
// throw new IllegalArgumentException("Source buffer is too small.");
// }
//
// deserializeOperationCodeByte(src.get());
//
// specificParameters = ByteBuffer.allocate(getLength().value());
// for (byte b = 0; b < getLength().value(); b++) {
// deserializeSpecificParameters(src.get());
// }
//
// deserializeControlByte(src.get());
//
// return src.position() - offset;
// }
//
// //
// --------------------------------------------------------------------------
// //
// --------------------------------------------------------------------------
//
// public final byte getGroupCode() {
//
// return (byte) (opCode & GROUP_CODE_MASK);
// }
//
// public final byte getCommandCode() {
//
// return (byte) (opCode & COMMAND_CODE_MASK);
// }
//
// public final boolean isLinkFlag() {
//
// return Utils.isBitSet(control & LINK_FLAG_MASK);
// }
//
// public final void setLinkFlag(final boolean newLinkFlag) {
//
// if (newLinkFlag) {
// control |= LINK_FLAG_MASK;
// } else {
// control &= ~LINK_FLAG_MASK;
// }
// }
//
// public final boolean isNACAFlag() {
//
// return Utils.isBitSet(control & NACA_FLAG_MASK);
// }
//
// public final void setNacaFlag(final boolean newNACAFlag) {
//
// if (newNACAFlag) {
// control |= NACA_FLAG_MASK;
// } else {
// control &= ~NACA_FLAG_MASK;
// }
// }
//
// public final GroupCode getLength() {
//
// GroupCode groupCode;
//
// switch (getGroupCode()) {
// case 0x00:
// groupCode = GroupCode.SIX_BYTE_COMMAND;
// break;
//
// case 0x01:
// case 0x02:
// groupCode = GroupCode.TEN_BYTE_COMMAND;
// break;
//
// case 0x04:
// groupCode = GroupCode.SIXTEEN_BYTE_COMMAND;
// break;
//
// case 0x05:
// groupCode = GroupCode.TWELVE_BYTE_COMMAND;
// break;
//
// case 0x06:
// case 0x07:
// groupCode = GroupCode.VENDOR_SPECIFIC;
//
// default:
// groupCode = null;
// }
//
// return groupCode;
// }
//
// // public final void setLength(final GroupCode groupCode) {
// // WRONG
// // opCode |= groupCode.value() << GROUP_CODE_SHIFT;
// // }
//
// public final int getTotalLength() {
//
// return getLength().value() + STANDARD_BYTES;
// }
//
// //
// --------------------------------------------------------------------------
// //
// --------------------------------------------------------------------------
//
// protected void deserializeOperationCodeByte(final byte b) {
//
// opCode = b;
// }
//
// protected void deserializeSpecificParameters(final byte b) {
//
// specificParameters.put(b);
// }
//
// protected void deserializeControlByte(final byte b) {
//
// control = b;
// }
//
// protected byte serializeOperationCodeByte() {
//
// return opCode;
// }
//
// protected byte serializeSpecificParameters() {
//
// return specificParameters.get();
// }
//
// protected byte serializeControlByte() {
//
// return control;
// }
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/** The Read Operation Code. */
private static final byte READ_OP_CODE = 0x28;
/** The Read Capacity Operation Code. */
private static final byte READ_CAPACITY_OP_CODE = 0x25;
/** The Write Operation Code. */
private static final byte WRITE_OP_CODE = 0x2A;
/** The byte index of the logical block address information. */
private static final int LOGICAL_BLOCK_ADDRESS_OFFSET = 2;
/** The byte index of the transfer length information. */
private static final int TRANSFER_LENGTH_OFFSET = 7;
/**
* Creates the Command Descriptor Block for a Read Message.
*
* @param logicalBlockAddress The Logical Block Address to begin the read operation.
* @param transferLength The transfer length field specifies the number of contiguous logical blocks of data to be
* transferred. A transfer length of zero indicates that 256 logical blocks shall be
* transferred. Any other value indicates the number of logical blocks that shall be transferred.
* @return A ByteBuffer object with the above data.
*/
public static final ByteBuffer createReadMessage (final int logicalBlockAddress, final short transferLength) {
return createReadWriteMessage(READ_OP_CODE, logicalBlockAddress, transferLength);
}
/**
* Creates the Command Descriptor Block for a Write Message.
*
* @param logicalBlockAddress The Logical Block Address to begin the read operation.
* @param transferLength The transfer length field specifies the number of contiguous logical blocks of data to be
* transferred. A transfer length of zero indicates that 256 logical blocks shall be transferred. Any
* other value indicates the number of logical blocks that shall be transferred.
* @return A ByteBuffer object with the above data.
*/
public static final ByteBuffer createWriteMessage (final int logicalBlockAddress, final short transferLength) {
return createReadWriteMessage(WRITE_OP_CODE, logicalBlockAddress, transferLength);
}
/**
* Creates the Command Descriptor Block for a given Operation Message.
*
* @param opCode The Operation Code.
* @param logicalBlockAddress The Logical Block Address to begin the read operation.
* @param transferLength The transfer length field specifies the number of contiguous logical blocks of data to be
* transferred. A transfer length of zero indicates that 256 logical blocks shall be transferred. Any
* other value indicates the number of logical blocks that shall be transferred.
* @return A ByteBuffer object with the above data.
*/
private static final ByteBuffer createReadWriteMessage (final byte opCode, final int logicalBlockAddress, final short transferLength) {
ByteBuffer cdb = ByteBuffer.allocate(DEFAULT_CDB_LENGTH);
// operation code
cdb.put(opCode);
// logical block address
cdb.position(LOGICAL_BLOCK_ADDRESS_OFFSET);
cdb.putInt(logicalBlockAddress);
// set transfer length
cdb.position(TRANSFER_LENGTH_OFFSET);
cdb.putShort(transferLength);
cdb.rewind();
return cdb;
}
/**
* Creates the Command Descriptor Block for a Read Capacity Message.
*
* @return A ByteBuffer object with the above data.
*/
public static final ByteBuffer createReadCapacityMessage () {
ByteBuffer cdb = ByteBuffer.allocate(DEFAULT_CDB_LENGTH);
// operation code
cdb.put(READ_CAPACITY_OP_CODE);
cdb.rewind();
return cdb;
}
}
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