Files
msd-core/tests
Dave fc9bd70aff fix: PID-liveness gate for the two core-path file locks (audit M1+M2)
The STATE.md write lock (acquireStateLock) and the .planning/ workspace lock
(withPlanningLock) stole contended locks on mtime age alone with no
process.kill(pid,0) liveness check, and mis-ordered stale-vs-wait so a
live-but-slow holder could be robbed mid-critical-section.

M1 (lost update / STATE.md corruption): a live writer whose critical section
ran past the stale threshold aged out and a waiter unlinked its lock and
acquired -> two writers in STATE.md's read-modify-write window. mtime is a
leaky proxy for "holder is alive"; it leaks under exactly the slow-holder
condition the lock guards against.

M2 (uncaught EEXIST): withPlanningLock's timeout fallback unconditionally
unlinked whatever lock existed (even a live holder's) and re-acquired OUTSIDE
any try -- a concurrent re-create raced a raw EEXIST out of the helper.

Fix backports capability-lock.cts's liveness gate (process.kill(pid,0) via a
_setLockProbes/_resetLockProbes test seam):
- acquireStateLock: steal when holder pid is DEAD (any age) OR age exceeds a
  deadman ceiling (60000ms, ABOVE maxWaitMs=30000) so a verified-live holder is
  never stolen within budget; garbage/legacy bodies stay recoverable.
- withPlanningLock: same gate in the EEXIST path (dead stolen promptly, live
  waited on); removed the unconditional force-steal -> clear timeout throw,
  which also closes M2 (no re-acquire outside try).

Uncontended path unchanged byte-for-behaviour; realClock + real process.kill
remain the defaults. Pid-reuse residual fails safe (waits/times out, never
corrupts) and recovers at the deadman ceiling.

Tests: TDD red->green via the clock + new pid-liveness probe seams (no
wall-clock; #453 deleted the race tests). 8 new behavioural tests across
tests/clock-seam.test.cjs and tests/planning-workspace.test.cjs; the prior
withPlanningLock timeout test rewritten to pin the no-force-steal contract.

Claude-Session: https://claude.ai/code/session_01R88n7Q54bAaVHFkDbbH1yz
2026-06-21 13:11:22 -04:00
..