RTC — Clarify contract between execution context and non-initialized components

Source: RTI (Rick Warren, [[MailTo(rick DOT warren AT SPAMFREE rti DOT com)]])

Severity: Minor

Disposition: Resolution Proposed

Summary

The behavior of various !ExecutionContext methods (start, stop, activate_component, deactivate_component) are not fully specified in the case where a component has either (a) never been initialized, or (b) been finalized.

Discussion

Resolution

The behavior should be as follows:

• A context should not be allowed to start until all of its components are initialized. A failure should be indicated with PRECONDITION_NOT_MET.
• Before a component can be finalized, all contexts in which it participates must be stopped. A failure should be indicated with PRECONDITION_NOT_MET.
• Attempting to activate or deactivate a component that is not initialized or has been finalized should fail with PRECONDITION_NOT_MET.

The following sequence diagrams are examples (thanks, Sakamoto-san):

[attachment:rtc-initialize-sequence.png] [[BR]] Initialize and start

[attachment:rtc-finalize-sequence.png] [[BR]] Stop and Finalize

– RickWarren, 2006/12/1

Revised Text

The behavior should be as follows:
· A context should not be allowed to start until all of its components are initialized. A failure should be indicated with PRECONDITION_NOT_MET.
· Before a component can be finalized, it must be detached from all contexts in which it participates. A failure should be indicated with PRECONDITION_NOT_MET.
· Attempting to activate or deactivate a component that is not initialized or has been finalized should fail with BAD_PARAMETER.