ctf: fix bits interpreted as bytes in index creation

[arfio]

What it does

Fix how packet contexts are mapped into memory. The packet context size was in bits not bytes, a division was added to fix that issue.

How to test

Use the following trace: the-trace.zip

Follow-ups

N/A

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the instructions in this template

Summary by CodeRabbit

• Bug Fixes
  • Fixed packet context indexing to ensure trace data is mapped using the correct byte-based size.
  • Improved reliability when reading and navigating CTF traces.

[coderabbitai]

📝 Walkthrough

Walkthrough

CTFTrace.createIndex now converts the packet-context size from bits to bytes before memory mapping.

Changes

Packet Context Index Mapping

Layer / File(s)	Summary
Convert packet-context size before mapping ctf/.../CTFTrace.java	createIndex uses the packet-context maximum size converted from bits to bytes when it creates the mapping.

Estimated code review effort: 1 (Trivial) | ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 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 fix for interpreting packet-context bits as bytes during index creation.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
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.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In
`@ctf/org.eclipse.tracecompass.ctf.core/src/org/eclipse/tracecompass/ctf/core/trace/CTFTrace.java`:
- Line 619: Update the packet mapping logic in CTFTrace so the bit-sized packet
context length is converted to bytes with ceiling alignment instead of
truncation. Adjust both the bounds check that compares against
packetPosition/getPacketHeader().getMaximumSize() and the
SafeMappedByteBuffer.map() byte-length argument using the same rounded-up byte
calculation. Keep the existing mapping flow intact, and make sure
packetContextDecl.getMaximumSize() remains the source of the size used in both
places.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: f5ef40d8-44de-4834-b740-8a827737109a

📥 Commits

Reviewing files that changed from the base of the PR and between 9708bb9 and ecce0ff.

📒 Files selected for processing (1)

• ctf/org.eclipse.tracecompass.ctf.core/src/org/eclipse/tracecompass/ctf/core/trace/CTFTrace.java