Initial commit

Signed-off-by: Ilan Bigio <ilan@openai.com>

codex-cli/src/utils/terminal.ts

@@ -0,0 +1,82 @@
+import type { Instance } from "ink";
+import type React from "react";
+
+let inkRenderer: Instance | null = null;
+
+// Track whether the clean‑up routine has already executed so repeat calls are
+// silently ignored. This can happen when different exit paths (e.g. the raw
+// Ctrl‑C handler and the process "exit" event) both attempt to tidy up.
+let didRunOnExit = false;
+
+export function setInkRenderer(renderer: Instance): void {
+  inkRenderer = renderer;
+
+  if (process.env["CODEX_FPS_DEBUG"]) {
+    let last = Date.now();
+    const logFrame = () => {
+      const now = Date.now();
+      // eslint-disable-next-line no-console
+      console.error(`[fps] frame in ${now - last}ms`);
+      last = now;
+    };
+
+    // Monkey‑patch the public rerender/unmount methods so we know when Ink
+    // flushes a new frame.  React’s internal renders eventually call
+    // `rerender()` so this gives us a good approximation without poking into
+    // private APIs.
+    const origRerender = renderer.rerender.bind(renderer);
+    renderer.rerender = (node: React.ReactNode) => {
+      logFrame();
+      return origRerender(node);
+    };
+
+    const origClear = renderer.clear.bind(renderer);
+    renderer.clear = () => {
+      logFrame();
+      return origClear();
+    };
+  }
+}
+
+export function clearTerminal(): void {
+  if (process.env["CODEX_QUIET_MODE"] === "1") {
+    return;
+  }
+
+  // When using the alternate screen the content never scrolls, so we rarely
+  // need a full clear. Still expose the behaviour when explicitly requested
+  // (e.g. via Ctrl‑L) but avoid unnecessary clears on every render to minimise
+  // flicker.
+  if (inkRenderer) {
+    inkRenderer.clear();
+  }
+}
+
+export function onExit(): void {
+  // Ensure the clean‑up logic only runs once even if multiple exit signals
+  // (e.g. Ctrl‑C data handler *and* the process "exit" event) invoke this
+  // function. Re‑running the sequence is mostly harmless but can lead to
+  // duplicate log messages and increases the risk of confusing side‑effects
+  // should future clean‑up steps become non‑idempotent.
+  if (didRunOnExit) {
+    return;
+  }
+
+  didRunOnExit = true;
+
+  // First make sure Ink is properly unmounted so it can restore any terminal
+  // state it modified (e.g. raw‑mode on stdin). Failing to do so leaves the
+  // terminal in raw‑mode after the Node process has exited which looks like
+  // a “frozen” shell – no input is echoed and Ctrl‑C/Z no longer work. This
+  // regression was introduced when we switched from `inkRenderer.unmount()`
+  // to letting `process.exit` terminate the program a few commits ago. By
+  // explicitly unmounting here we ensure Ink performs its clean‑up logic
+  // *before* we restore the primary screen buffer.
+  if (inkRenderer) {
+    try {
+      inkRenderer.unmount();
+    } catch {
+      /* best‑effort – continue even if Ink throws */
+    }
+  }
+}