claude-print/notes/bf-2w7.md

Cleanup Implementation Verification (bf-2w7)

Task

Always tear down temp dir + stop.fifo on every exit path; sweep orphans on startup

Implementation Status: COMPLETE

All cleanup mechanisms were already properly implemented in the codebase.

Exit Paths Covered

1. Normal Exit (Success)

• Location: main.rs:189
• Mechanism: Calls exit_with_cleanup(0) → cleanup_temp_dir()
• Coverage: ✓ Cleanups before process::exit(0)

2. Normal Exit (Error)

• Location: Various paths in main.rs
• Mechanism: Calls exit_with_cleanup(2-4) → cleanup_temp_dir()
• Coverage: ✓ Cleanups before process::exit()

3. Timeout Exit

• Location: main.rs:211
• Mechanism: Calls exit_with_cleanup(124) → cleanup_temp_dir()
• Coverage: ✓ Cleanups watchdog timeout exits

4. Signal Interruption (SIGINT/SIGTERM)

• Location: main.rs:200
• Mechanism: Calls exit_with_cleanup(130) → cleanup_temp_dir()
• Coverage: ✓ Cleanups after signal handling

5. Watchdog Timeout

• Location: watchdog.rs:286-299
• Mechanism: Watchdog kills child → returns Error::Timeout → exit_with_cleanup()
• Coverage: ✓ Ensures cleanup on watchdog timeout

6. Panic During Session

• Location: session.rs:114
• Mechanism: catch_unwind ensures CleanupGuard::drop runs
• Coverage: ✓ Cleanup even on panic

7. Early Returns

• Location: Throughout session.rs
• Mechanism: CleanupGuard drops on early return
• Coverage: ✓ Cleanup on early exit paths

Cleanup Mechanisms

1. Orphan Cleanup on Startup

• Function: hook.rs:17 - cleanup_orphans()
• Called from: main.rs:39
• Behavior:
  • Sweeps system temp directory for claude-print-* patterns
  • Removes directories older than 10 minutes (600 seconds)
  • Removes FIFO first, then entire directory
• Coverage: ✓ Prevents accumulation of orphans from crashes

2. CleanupGuard (Drop-based cleanup)

• Location: session.rs:43-49
• Behavior:
  • Calls installer.cleanup() on drop
  • Covers all paths where guard goes out of scope
  • Idempotent via atomic flag
• Coverage: ✓ Automatic cleanup via RAII

3. Global Cleanup Before Exit

• Function: session.rs:55 - cleanup_temp_dir()
• Called from: main.rs:31 via exit_with_cleanup()
• Behavior:
  • Removes FIFO first (may have different permissions)
  • Removes entire temp directory with retry logic (3 attempts)
  • Handles process::exit() bypassing destructors
• Coverage: ✓ Explicit cleanup before exit

4. Idempotent Cleanup

• Location: hook.rs:116-146
• Mechanism: Atomic flag cleanup_performed
• Behavior:
  • Prevents double-free with atomic swap
  • Safe to call multiple times
  • Explicit FIFO removal before directory
  • Retry logic for transient failures (3 attempts)
• Coverage: ✓ Safe cleanup even if called multiple times

Verification

Tests Passing

• ✓ cleanup_explicitly_removes_fifo
• ✓ cleanup_can_be_called_multiple_times
• ✓ cleanup_orphans_does_not_panic
• ✓ temp_dir_cleaned_up_on_drop

No Orphaned Directories Found

$ ls -la /tmp/claude-print-* 2>/dev/null
(no output - all cleaned up)

Architecture

The cleanup strategy uses defense in depth:

1. Startup sweep: Removes old orphans from previous crashes
2. RAII guard: Automatic cleanup via Drop trait
3. Explicit cleanup: Manual cleanup before process::exit()
4. Idempotency: Safe to call cleanup multiple times
5. Retry logic: Handles transient filesystem issues

This ensures temp directories and FIFOs are removed on all exit paths:

• Normal exit (success)
• Normal exit (error)
• Timeout (watchdog)
• Signal interruption (SIGINT/SIGTERM)
• Panic
• Early returns

Conclusion

The implementation is complete and verified. All exit paths properly tear down temporary resources, and orphan cleanup runs on startup to prevent accumulation from crashed runs.