[20227] Prevent index overflow and correctly assert the end iterator in DataSharing

[Mario-DL]

Description

When a DataSharing compatible publisher and subscriber were launched at high frequency (publication interval set to 0), it happened two different issues:

• The current notified_end of the segment iterator was being updated before being actually checked, making an assert() compare two different versions of this iterator.
• On the other hand, unrelated with the previous observation, a corner case of advancing twice the next_payload_ counter could occur.

Apart from the included test, in order to reproduce the first issue it is enough to launch a BasicConfigurationExample with a bounded type and no sleep betweenwrites(). Launching, killing and relaunching the subscriber should trigger the assertion.
For reproducing the second issue, launch the subscriber first and then the publisher, a SIGSEV will be triggered in 20 seconds or so.

This PR includes two fixes that mitigate the problem.
The idea of the test is that if in 20 seconds we have not crashed by some of the above issues, we give the test as passed.

Important note It was noticed that enabling all the verbosity messages in the test, makes the test not work properly under colcon since the timeout notification of the SubscriberModule.cpp condition variable is never fired. It seems that the test stresses the cpu and the timeout notification is lost. However, if the python3 is directly invoked from a terminal (outside colcon), then there is no problem even if all the logs are enabled.

@Mergifyio backport 2.12.x 2.11.x 2.10.x 2.6.x

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• N/A Any new/modified methods have been properly documented using Doxygen.
• [X ] Changes are ABI compatible.
• Changes are API compatible.
• N/A New feature has been added to the versions.md file (if applicable).
• N/A New feature has been documented/Current behavior is correctly described in the documentation.
• Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.

[Mario-DL]

@richiprosima please test linux

[Mario-DL]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test discovery_server

[Mario-DL]

@richiprosima please test mac

[EduPonz]

NIT not requiring CI

[Mario-DL]

@richiprosima please test this

[EduPonz]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[EduPonz]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[Mario-DL]

@richiprosima please test mac

[JesusPoderoso]

CI issues unrelated to the PR. Ready to merge!

[MiguelCompany]

@Mergifyio backport 2.12.x 2.10.x 2.6.x

[mergify]

backport 2.12.x 2.10.x 2.6.x

✅ Backports have been created

• #4402 [20227] Prevent index overflow and correctly assert the end iterator in DataSharing (backport #4321) has been created for branch 2.12.x
• #4403 [20227] Prevent index overflow and correctly assert the end iterator in DataSharing (backport #4321) has been created for branch 2.10.x
• #4404 [20227] Prevent index overflow and correctly assert the end iterator in DataSharing (backport #4321) has been created for branch 2.6.x but encountered conflicts