Function detectAutopilot

lib/gbrain-guards.ts:82–114

(
  env: NodeJS.ProcessEnv = process.env,
  probe: AutopilotProbe = {},
)

 * normal syncs are never bricked.
 */
export function detectAutopilot(
  env: NodeJS.ProcessEnv = process.env,
  probe: AutopilotProbe = {},
): AutopilotStatus {
  // Secondary signal: known lock files. gbrain #1226 — the lock ignores
  // GBRAIN_HOME, so check both the configured home and the default ~/.gbrain.
  const lockPaths = probe.lockPaths ?? [
    join(gbrainHome(env), "autopilot.lock"),
    join(homedir(), ".gbrain", "autopilot.lock"),
    join(gbrainHome(env), "autopilot.pid"),
    join(homedir(), ".gbrain", "autopilot.pid"),
  ];
  for (const lp of lockPaths) {
    if (!existsSync(lp)) continue;
    // A lock FILE alone is not proof of life — a crashed daemon leaves a stale
    // lock that would otherwise wedge every sync forever (observed: a dead pid
    // refused --full indefinitely). Read the holder pid and check liveness.
    const pid = readLockPid(lp);
    if (pid === null) {
      // Can't introspect (no parseable pid) → stay conservative: treat as active.
      return { active: true, signal: `lock:${lp}` };
    }
    if (isPidAlive(pid)) {
      return { active: true, signal: `lock:${lp} (pid ${pid})` };
    }
    // Stale lock (holder pid is dead): ignore this signal, keep checking. Pure
    // decision function — we do NOT delete the file here; the caller may clean it.
  }
  // Primary signal: a live `gbrain autopilot` process.
  const running = (probe.processRunning ?? defaultProcessRunning)();
  if (running) return { active: true, signal: "process:gbrain autopilot" };
  return { active: false, signal: null };
}

/** Read the holder pid from a lock/pid file. Returns null if no integer pid is present. */
function readLockPid(lockPath: string): number | null {