tests: synchronize S3 runtime chunk setup

[cosmo0920]

Patched tests/runtime/out_s3.c line 265.

All three logs show SIGSEGVs in two tests sharing an unsafe pattern: a disk file becomes visible before its in-memory S3 object is ready. The tests accessed that object without the worker’s mutex.

Both now wait for registration and access the object under the mutex. Timeout paths fail cleanly instead of dereferencing a missing object.

Verification passed:

• Full build and ctest --test-dir build -R '^flb-rt-out_s3$' --output-on-failure.
• Five repeated runs of both affected cases.
• Both cases under Valgrind: zero errors or lost bytes.
• S3 integration: 19 passed, 6 skipped.
• Strict Valgrind retry integration: 7 passed.

Exact integration commands used:

PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python tests/integration/.venv/bin/python -m pytest tests/integration/scenarios/out_s3/tests/test_out_s3_001.py -q

VALGRIND=1 VALGRIND_STRICT=1 PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python tests/integration/.venv/bin/python -m pytest tests/integration/scenarios/out_s3/tests/test_out_s3_001.py -k retry -q

The six skips cover unsupported columnar formats and OTLP metrics/traces uploads.

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Testing
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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

Summary by CodeRabbit

• Tests
  • Improved coverage for S3 file creation timing and ordered upload retry scenarios.
  • Updated test setup and cleanup paths to provide more reliable validation of shared uploads and exhausted chunk conditions.
  • Preserved existing behavior across other S3 test cases while standardizing file lookup handling.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Advanced

Run ID: 6ee5870d-a4cd-4eb9-adf6-29c9cba23c94

📥 Commits

Reviewing files that changed from the base of the PR and between a48daa6 and c383eed.

📒 Files selected for processing (1)

• tests/runtime/out_s3.c

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📝 Walkthrough

Walkthrough

The S3 runtime test helper now optionally copies the located file name into a caller buffer. Two ordered-upload tests use this helper and add cleanup paths for early failures.

Changes

S3 runtime test updates

Layer / File(s)	Summary
Extend S3 file wait helper tests/runtime/out_s3.c	wait_for_s3_file_create_time optionally copies the located file name. Existing callers pass no output buffer.
Migrate ordered upload tests tests/runtime/out_s3.c	The ordered-upload tests use the helper for file and create-time setup. Early failures now jump to cleanup paths. The shared-upload test retains its distinct-chunk check.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Other

Suggested reviewers: singholt

Merge Risk: ⚪ Minimal · up to c383e

The S3 runtime test synchronization update has no identified merge-blocking risk.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 5 functions across 1 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: synchronizing S3 runtime chunk setup in the affected tests.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-18T09:28:42.177896Z	c383eed	Draft marked ready

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