rdmbair13m5-changelog-20260904-2025-m1-ecsprocess-ecspersistence-remediation

Remediated critical concurrency, timeout escalation, binary preservation, and pipe hang defects in ECSProcess, fixed transactionDepth state leak in ECSPersistence, verified 93/93 tests passing under ThreadSanitizer locally and on rdmsm4x, and pushed clean commits to git.ecs0.net and GitHub.

• Date: 2026-09-04 20:25:00 EDT
• Host: rdmbair13m5 (promoted to rdmsm4x)
• Scope: ~/dev/lib/ECSProcess, ~/dev/lib/ECSPersistence
• Remediations:
  1. ECSProcess Concurrency: Replaced actor-blocking synchronous waitUntilExit() with asynchronous suspension using ProcessExitCoordinator (withCheckedContinuation on process.terminationHandler) and made run entry points nonisolated. Verified concurrent tasks run in 0.51s instead of 2.04s.
  2. ECSProcess Timeout Escalation: Implemented two-stage timeout in timeoutTask sending SIGTERM, waiting 500ms grace period, and escalating to kill(process.processIdentifier, SIGKILL) if still running. Throws ProcessRunnerError.processTimedOut(timeoutSeconds). Verified trapped SIGTERM processes terminate in 1.54s instead of hanging for 5.11s.
  3. ECSProcess Binary Preservation: Updated ProcessResult to store raw standardOutput: Data, standardError: Data, and combinedData: Data, providing stdout, stderr, and combinedOutput as computed UTF-8 properties. Verified non-UTF8 binary byte streams (3,072 bytes) are fully preserved.
  4. ECSProcess Pipe Hang: Replaced synchronous readDataToEndOfFile() with drainNonBlocking utilizing O_NONBLOCK POSIX file descriptor reads. Verified subprocesses with orphaned background children holding pipe open return in 0.03s instead of hanging for 4.07s.
  5. ECSPersistence transactionDepth Fix: Corrected transactionDepth pre-increment leak in ECS0Persistence.swift by incrementing only after execDirect succeeds and applying defer { transactionDepth -= 1 }. Added public var currentTransactionDepth: Int.
• Verification Evidence:
  • swift test --sanitize=thread on ECSProcess: 22/22 tests pass locally (6.210s) and on rdmsm4x (6.248s).
  • swift test --sanitize=thread on ECSPersistence: 13/13 tests pass locally (0.284s) and on rdmsm4x (0.321s).
  • Full Tier 0 sweep on rdmsm4x: 93/93 tests pass with 0 failures, 0 warnings, and 0 TSAN race conditions.
• Git Commits & Remotes:
  • ECSProcess: commit dcd8550 pushed to git.ecs0.net:git/lib/ECSProcess.git (main) and github.com/richhdoty/rdmsm4x-dev-lib-ecsprocess.git (main).
  • ECSPersistence: commit c9002b0 pushed to git.ecs0.net:git/lib/ECSPersistence.git (main) and github.com/richhdoty/rdmsm4x-dev-lib-ecspersistence.git (main).
  • Canonical rdmsm4x:~/dev/lib/ fast-forwarded and verified clean.