1 package org.jscsi.target.scsi.sense;
2
3
4 import org.jscsi.target.scsi.ISerializable;
5
6
7 /**
8 * Sense data shall be returned in the same I_T_L_Q nexus transaction as a CHECK CONDITION status and as parameter data
9 * in response to the REQUEST SENSE command.
10 * <p>
11 * Sense data returned in the same I_T_L_Q nexus transaction as a CHECK CONDITION status shall be either fixed or
12 * descriptor format sense data format based on the value of the D_SENSE bit in the Control mode page.
13 * <p>
14 * The REQUEST SENSE command may be used to request either the fixed format sense data or the descriptor format sense
15 * data.
16 *
17 * @author Andreas Ergenzinger
18 */
19 public abstract class SenseData implements ISerializable {
20
21 /**
22 * The first byte of all sense data contains the RESPONSE CODE field that indicates the error type and format of the
23 * sense data.
24 *
25 * @see #errorType
26 * @see #senseDataFormat
27 */
28 protected final int responseCode;
29
30 /**
31 * The error type of the sense data as determined by the {@link #responseCode} variable.
32 */
33 protected final ErrorType errorType;
34
35 /**
36 * The format of the sense data as determined by the {@link #responseCode} variable.
37 */
38 protected final SenseDataFormat senseDataFormat;
39
40 /**
41 * The {@link #senseKey} and {@link #additionalSenseCodeAndQualifier} fields provide a hierarchy of information. The
42 * hierarchy provides a top-down approach for an application client to determine information relating to the error
43 * and exception conditions.
44 */
45 protected final SenseKey senseKey;
46
47 /**
48 * The {@link #senseKey} and {@link #additionalSenseCodeAndQualifier} fields provide a hierarchy of information. The
49 * hierarchy provides a top-down approach for an application client to determine information relating to the error
50 * and exception conditions.
51 */
52 protected final AdditionalSenseCodeAndQualifier additionalSenseCodeAndQualifier;
53
54 /**
55 * The sense data constructor.
56 *
57 * @param errorType the error type of the sense data
58 * @param senseDataFormat the format of the sense data
59 * @param senseKey describes the general category of the error requiring the sending of sense data
60 * @param additionalSenseCodeAndQualifier a more specific description of the error
61 */
62 public SenseData (final ErrorType errorType, final SenseDataFormat senseDataFormat, final SenseKey senseKey, final AdditionalSenseCodeAndQualifier additionalSenseCodeAndQualifier) {
63 this.errorType = errorType;
64 this.senseDataFormat = senseDataFormat;
65 responseCode = getReponseCodeFor(errorType, senseDataFormat);
66 this.senseKey = senseKey;
67 this.additionalSenseCodeAndQualifier = additionalSenseCodeAndQualifier;
68 }
69
70 /**
71 * Returns the proper response code for the given error type and sense data format.
72 *
73 * @param errorType a sense data error type
74 * @param senseDataFormat a sense data format
75 * @return the proper response code
76 */
77 public static final int getReponseCodeFor (final ErrorType errorType, final SenseDataFormat senseDataFormat) {
78 if (senseDataFormat == SenseDataFormat.FIXED) {
79 if (errorType == ErrorType.CURRENT)
80 return 0x70;
81 else
82 // errorType == DEFERRED
83 return 0x71;
84 } else {// senseDataFormat == DESCRIPTOR
85 if (errorType == ErrorType.CURRENT)
86 return 0x72;
87 else
88 // errorType == DEFERRED
89 return 0x73;
90 }
91 /*
92 * Response codes 0x74 to 0x7E are reserved. Response code 0x7f is vendor specific.
93 */
94 }
95 }