fix(rp2040): cancel timed-out UF2 writes

[zackees]

Summary

• cancel synchronous Windows UF2 writes after a watchdog timeout and wait briefly for the destination handle to close
• report live abandoned-worker count and oldest age when a worker cannot stop within the grace period
• cover timeout diagnostics and worker recovery

Closes #1164

Validation

• soldr cargo test -p fbuild-deploy watchdog -- --nocapture (3 passed)
• soldr rustfmt --check crates/fbuild-deploy/src/rp2040.rs`n

Note

• soldr cargo clippy -p fbuild-deploy --all-targets -- -D warnings is blocked by an existing unrelated build-serial unused import: GUID_DEVCLASS_USB.

Summary by CodeRabbit

• Bug Fixes

  • Improved deployment reliability when UF2 writes exceed the watchdog timeout.
  • Added Windows-specific cancellation handling for stalled file operations.
  • Enhanced timeout diagnostics with information about unfinished operations.

• Tests

  • Added coverage for stalled operations and verification that diagnostics clear after recovery.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: f5b3f084-acf8-4307-8921-93f5e0910757

📥 Commits

Reviewing files that changed from the base of the PR and between 16bb9ff and 712db0b.

⛔ Files ignored due to path filters (1)

• Cargo.lock is excluded by !**/*.lock

📒 Files selected for processing (2)

• crates/fbuild-deploy/Cargo.toml
• crates/fbuild-deploy/src/rp2040.rs

---

📝 Walkthrough

Walkthrough

RP2040 watchdog handling now tracks worker lifecycles, cancels Windows synchronous I/O after timeouts, reports abandoned-worker diagnostics, and validates eventual cleanup with a blocking-worker test.

Changes

RP2040 watchdog recovery

Layer / File(s)	Summary
Watchdog tracking and Windows support crates/fbuild-deploy/Cargo.toml, crates/fbuild-deploy/src/rp2040.rs	Adds Windows I/O support and a shared registry for tracking watchdog workers and abandonment ages.
Timeout cancellation and cleanup validation crates/fbuild-deploy/src/rp2040.rs	Adds bounded cancellation handling, diagnostic timeout errors, and a test covering abandonment followed by worker completion.

Estimated code review effort: 4 (Complex) | ~45 minutes

Possibly related issues

• FastLED/FastLED issue 3630 — Covers end-to-end RP2040 watchdog recovery and deployment soak testing.
• FastLED/fbuild issue 1161 — Tracks the related watchdog timeout cleanup and worker termination changes.
• FastLED/fbuild issue 1166 — Addresses stalled Windows mass-storage writes and abandoned worker cleanup.

Possibly related PRs

• FastLED/fbuild#1041 — Introduces the RP2040 UF2 deployment behavior extended by these watchdog changes.
• FastLED/fbuild#1083 — Previously modified UF2 watchdog and write-timeout handling in the same deployment module.

Sequence Diagram(s)

sequenceDiagram
  participant Deployer
  participant WatchdogWorker
  participant WindowsIO
  Deployer->>WatchdogWorker: Start UF2 write and register worker
  Deployer->>WindowsIO: Cancel synchronous I/O after timeout
  WindowsIO-->>WatchdogWorker: Cancellation request
  WatchdogWorker-->>Deployer: Complete within grace period or remain blocked
  Deployer->>Deployer: Record abandonment and include diagnostics

Loading

🚥 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 accurately summarizes the main change: handling timed-out RP2040 UF2 writes by canceling them.
Linked Issues check	✅ Passed	The changes match #1164 by canceling timed-out Windows writes, adding bounded wait/abandonment tracking, and covering diagnostics and recovery.
Out of Scope Changes check	✅ Passed	The edits stay focused on RP2040 deploy timeout handling plus the needed Windows dependency addition, with no clear unrelated scope.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/rp2040-watchdog-handle

---

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.}