[23974] Fix DataReader history enforcement to respect max_samples_per_instance

[raulojeda22]

Description

This PR fixes a bug where DataReader was incorrectly using history.depth instead of max_samples_per_instance when depth > max_samples_per_instance.

Current Behavior (Bug)

When a DataReader is configured with:

• history.depth = 10
• max_samples_per_instance = 5

The QoS validation correctly warns:

HISTORY DEPTH '10' is inconsistent with max_samples_per_instance: '5'. 
Effectively using max_samples_per_instance as depth.

However, the DataReader was actually storing 10 samples (using depth) instead of 5 (using max_samples_per_instance), making the warning misleading.

Root Cause

The bug existed in three locations:

1. DataReaderHistory constructor: For NO_KEY topics, max_samples_per_instance was being overwritten with max_samples, destroying the user's QoS setting
2. DataReaderHistory::received_change_keep_last: Was checking instance_changes.size() < depth instead of instance_changes.size() < min(depth, max_samples_per_instance)
3. DataReaderHistory::completed_change_keep_last: Same issue for fragmented samples

Changes

• Fixed all three locations to use min(history.depth, max_samples_per_instance) as the effective limit
• Updated DataWriterHistory::to_history_attributes for consistency in memory allocation
• Added unit tests covering:
  • NO_KEY topics (critical case where constructor was overwriting QoS)
  • WITH_KEY topics

Impact

This fix ensures the DataReader behavior matches the documented QoS warning message. Applications relying on max_samples_per_instance to limit memory usage will now work correctly.

@Mergifyio backport 3.4.x 3.2.x 2.14.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
• Any new/modified methods have been properly documented using Doxygen.
• N/A Any new configuration API has an equivalent XML API (with the corresponding XSD extension)
• Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• Changes are API compatible.
• N/A New feature has been added to the versions.md file (if applicable).
• New feature has been documented/Current behavior is correctly described in the documentation.
  • Related documentation PR: [23974] Better explanation for depth vs mspi behavior Fast-DDS-docs#1194
• 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.
• N/A: If this is a critical bug fix, backports to the critical-only supported branches have been requested.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.

[mergify]

🧪 CI Insights

Here's what we observed from your CI run for 5b0f1ee.

❌ Job Failures

Pipeline	Job	Health on 3.4.x	Retries	🔍 CI Insights	📄 Logs
Fast DDS MacOS CI	mac-ci / fastdds_test ()		0	View	View
Fast DDS Ubuntu CI	ubuntu-ci / fastdds_test (RelWithDebInfo)		0	View	View
Fast DDS Windows CI	windows-ci / fastdds_test (RelWithDebInfo, examples), v142		0	View	View
	windows-ci / fastdds_test (RelWithDebInfo, examples), v143		0	View	View

[MiguelCompany]

Apart from the comment below, remember to clarify the documentation (i.e. do a partial backport of eProsima/Fast-DDS-docs#1188)

[MiguelCompany]

LGTM with green CI

[MiguelCompany]

@Mergifyio backport 3.4.x 3.2.x 2.14.x

[mergify]

backport 3.4.x 3.2.x 2.14.x

✅ Backports have been created

Details

• Backport to branch 3.4.x completed

No pull request needed: No commits between 3.4.x and mergify/bp/3.4.x/pr-6228

• #6284 [23974] Fix DataReader history enforcement to respect max_samples_per_instance (backport #6228) has been created for branch 3.2.x but encountered conflicts

Cherry-pick of 30b6351 has failed:

On branch mergify/bp/3.2.x/pr-6228
Your branch is up to date with 'origin/3.2.x'.

You are currently cherry-picking commit 30b63511.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   src/cpp/fastdds/publisher/DataWriterHistory.cpp
	modified:   src/cpp/fastdds/publisher/DataWriterImpl.cpp
	modified:   src/cpp/fastdds/subscriber/DataReaderImpl.cpp
	modified:   src/cpp/fastdds/subscriber/history/DataReaderHistory.cpp
	modified:   src/cpp/rtps/history/HistoryAttributesExtension.hpp
	modified:   test/mock/dds/DataWriterHistory/fastdds/publisher/DataWriterHistory.hpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   test/unittest/dds/subscriber/DataReaderTests.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

• #6285 [23974] Fix DataReader history enforcement to respect max_samples_per_instance (backport #6228) has been created for branch 2.14.x but encountered conflicts

Cherry-pick of 30b6351 has failed:

On branch mergify/bp/2.14.x/pr-6228
Your branch is up to date with 'origin/2.14.x'.

You are currently cherry-picking commit 30b63511d.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   src/cpp/fastdds/subscriber/history/DataReaderHistory.cpp
	modified:   src/cpp/rtps/history/HistoryAttributesExtension.hpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   src/cpp/fastdds/publisher/DataWriterHistory.cpp
	both modified:   src/cpp/fastdds/publisher/DataWriterImpl.cpp
	both modified:   src/cpp/fastdds/subscriber/DataReaderImpl.cpp
	both modified:   test/mock/rtps/PublisherHistory/fastdds/publisher/DataWriterHistory.hpp
	both modified:   test/unittest/dds/subscriber/DataReaderTests.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally