PH67801: NEGATIVE VALUE DISPLAYED FOR EXPIRE DATE/DAYS IN ZOSMF STORAGE MANAGEMENT PLUGIN

APAR status

• Closed as program error.

Error description

• Negative value displayed for Expire Date/Days in zOSMF Storage
  management plugin when the value set in the Management class is
  higher than 32768; similar issue in Data class 'Retention
  absolute day of the year' which was causing negative value to
  be displayed in UI beyond 32768.
  
  KNOWN IMPACT:
  The only impact is incorrect display in the Storage management
  plugin. The system works correctly under the covers and
  displaying the same value from ISMF works correctly.
  

Local fix

• BYPASS/CIRCUMVENTION:
  Use ISMF to see the correct value
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All user of Storage management plugin GUI    *
  *                 and users of Storage management REST APIs in *
  *                 3.2.                                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: Negative value displayed for Expire     *
  *                      Date/Days in zOSMF Storage              *
  *                      management plugin when the value set    *
  *                      in the Management class is              *
  *                      higher than 32768; similar issue in     *
  *                      Data class 'Retention                   *
  *                      absolute day of the year' which was     *
  *                      causing negative value to               *
  *                      be displayed in UI beyond 32768.        *
  *                                                              *
  *                      KNOWN IMPACT:                           *
  *                      The only impact is incorrect display    *
  *                      in the Storage management               *
  *                      plugin. The system works correctly      *
  *                      under the covers and displaying the     *
  *                      same value from ISMF works correctly.   *
  ****************************************************************
  

Problem conclusion

• The system incorrectly handled "Expiry date/days" fields,
  causing data overflow and misinterpretation when retention
  period values exceeded the capacity of 2-byte storage, despite
  the valid range extending to 93,000 days.
  
  Solution Architecture
  
  1. Context-Aware Data Type Management
  - Implemented dynamic data type selection based on SMS-returned
  format indicators
  - Upgraded from 2-byte to 4-byte integer storage to accommodate
  full value range
  - Format interpretation distinguishes between date-based and
  day-count representations
  - 32-bit Value Extraction: Conditionally extracts different bit
  segments from the 32-bit integer:
  - Date mode: Splits into separate 8-bit and 16-bit components
  for year and day-of-year
  - Day-count mode: Extracts equal-sized bit segments
  (24-bit value) for total days
  - Bit selection driven by format flags to ensure correct
  interpretation
  
  2. NOLIMIT Case Handling
  - Corrected flag-based detection logic for unlimited retention
  scenarios
  - Introduced internal tracking mechanism using existing API
  field
  - Propagates NOLIMIT status consistently across API responses
  and UI display to existing 'Format used for retention' field
  Requires CDD and Swagger documentation updates
  
  3. Flag-Based Validation Framework
  - Hierarchical validation approach checking presence, special
  cases, and format type
  - Date format: Validates year and day-of-year components
  extracted from different bit positions
  - Day-count format: Applies bit masking to extract lower 24
  bits, validates range [0, 93,000]
  - Graceful degradation: Logs errors without failing API calls
  for problematic entries
  
  4. UI Layer Adaptations
  - Converted numeric fields to string type for flexible value
  representation
  - Updated filter mechanisms to handle string-based comparisons
  - Supports display of both numeric values and special indicators
  (e.g., NOLIMIT)
  
  5. Multi-Layer Technical Implementation
  - C Layer: Reads full 32-bit values from SMS, applies flag-based
   conditional processing with selective bit extraction
  - JNI Boundary: Updated field signatures and transfer methods
  for 32-bit integers
  - Java Layer: Modified field types and accessor methods to
  handle extended range
  - Bit-Level Processing: Conditional extraction of 8-16 bit
  segments (date mode) or equal 24-bit segments (day-count mode)
  from 32-bit source
  
  6. Documentation Requirements
  - Component Design Document updates for field specifications
  - API documentation (Swagger) schema changes
  - Programming guide updates for validation logic
  - User-facing help documentation revisions
  
  7. Key Outcomes
  - Eliminates overflow errors for large retention periods
  - Ensures correct interpretation through conditional bit
  extraction
  - Maintains type safety with appropriate data structures
  - Implements non-disruptive error handling
  - Achieves consistency across system layers (C/JNI/Java/UI)
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UO07781

Modules/Macros

• IZUSGBIN IZUSGEAR IZUSGHLP IZUSGJ64 IZUSGUTL
  

Fix information

• Fixed component name

  Z/OSMF DFSMS ST

• Fixed component ID

  5655S28SG

Applicable component levels