DDS-XTypes 1.2 RTF Avatar
  1. OMG Issue

DDSXTY12 — Keyhash computation not well-defined for mutable types

  • Key: DDSXTY12-47
  • Status: closed  
  • Source: Real-Time Innovations ( Sumant Tambe)
  • Summary:

    Keyhash computation is not specified precisely enough. For instance, for mutable types it is not clear whether to use short/long parameter IDs and for PID_SENTINEL whether to set must-understand bit = 1/0? As a result, the keyhash for the same key may be different from different vendors.

  • Reported: DDS-XTypes 1.1 — Fri, 9 Oct 2015 20:53 GMT
  • Disposition: Resolved — DDS-XTypes 1.2
  • Disposition Summary:

    Update keyhash computation for mutable types

    Removed ambiguities from keyhash computation algorithm for mutable types. Specifically the following ambiguities existed.

    1. Whether to use short/long parameter encapsulation
    2. What's the value of must-understand bit in PID_SENTINEL.

    Both ambiguities are avoided using the revised algorithm.

  • Updated: Thu, 22 Jun 2017 16:42 GMT