Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

ui-tui/src/lib/parentLog.ts

@@ -0,0 +1,59 @@
+import { appendFileSync, mkdirSync } from 'node:fs'
+import { homedir } from 'node:os'
+import { join } from 'node:path'
+
+// Mirror the Python gateway's panic log (tui_gateway/server.py::_CRASH_LOG) from
+// the Node parent so lifecycle breadcrumbs interleave, by timestamp, with the
+// child's `=== SIGTERM received ===` / `=== gateway exit ===` entries.
+//
+// A backend SIGTERM is *usually* a parent action — `gw.kill()` (graceful-exit on
+// a signal to Node, or an explicit /quit) or `start()` replacing a live child —
+// but it can also come straight from an external supervisor (s6, a cgroup OOM
+// reaper, a stray `kill`) signalling the child directly. Telling those apart is
+// exactly the point: #31051 left these breadcrumbs in an in-memory CircularBuffer
+// that dies with the process, so SIGTERM crash reports arrived with no parent
+// context. A `[tui-parent]` line immediately before the child's panic means a
+// parent kill; its absence *suggests* an external signal — not definitive,
+// since this logger is best-effort (disabled under VITEST, and a failed append
+// is swallowed). Persisting the death-explaining events here is what makes that
+// distinction (and a memory-critical `process.exit(137)`, which closes stdin →
+// clean EOF, not SIGTERM) diagnosable after the fact.
+const logDir = join(process.env.HERMES_HOME?.trim() || join(homedir(), '.hermes'), 'logs')
+const CRASH_LOG = join(logDir, 'tui_gateway_crash.log')
+
+// Skipped under vitest so unit tests exercising start()/kill() can't write into
+// a real ~/.hermes (tests must stay hermetic — see AGENTS.md).
+const enabled = !process.env.VITEST
+// Slice a single breadcrumb's value to MAX_BREADCRUMB chars (a short
+// "[truncated …]" marker is appended, so the written line is slightly longer)
+// so a pathological value (e.g. a giant error) can't bloat the shared crash log
+// or add noticeable blocking on the synchronous append. Mirrors the spirit of
+// GatewayClient's in-memory log-line cap.
+const MAX_BREADCRUMB = 4096
+let warned = false
+
+export function recordParentLifecycle(line: string): void {
+  if (!enabled) {
+    return
+  }
+
+  try {
+    // Collapse embedded newlines so a multi-line value (e.g. an error message)
+    // stays one breadcrumb and can't masquerade as a separate log entry or as
+    // the child's panic output sharing this file.
+    const oneLine = line.replace(/[\r\n]+/g, ' ↵ ')
+
+    const capped =
+      oneLine.length > MAX_BREADCRUMB
+        ? `${oneLine.slice(0, MAX_BREADCRUMB)}… [truncated ${oneLine.length} chars]`
+        : oneLine
+
+    mkdirSync(logDir, { recursive: true })
+    appendFileSync(CRASH_LOG, `[tui-parent] ${new Date().toISOString()} ${capped}\n`)
+  } catch {
+    if (!warned) {
+      warned = true
+      process.stderr.write('hermes-tui: parent lifecycle log unavailable\n')
+    }
+  }
+}