A registry of per-connection locks, acquired (interruptibly) before
spawning a worker and released by whichever side finishes last, so an
abandoned call's worker is never running concurrently with a new call
on the same connection. Uses a POSIX semaphore (sem_t), not a mutex:
review round 1 found the initial pthread_mutex_t implementation relied
on behavior POSIX classifies as undefined for a non-owning-thread
unlock (not just error-checking mutex types) -- this design's worker
thread legitimately releases a lock the caller thread acquired, which
sem_t supports with no ownership concept at all. bug-1791. Design.md
synced to reflect the semaphore choice. 1285/1285 controller suite
passing.
Task 1.5 of .kiro/specs/xce-test-cli-ux/tasks.md.
Requirements: 1.1, 1.5
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019jaMf9QEwpugH2W9KAuc7f
