fix(tui): exited when terminal disconnected

Stopped the renderer when stdin closes or stdout fails, then raised SIGHUP so registered session cleanup completes before exit.

Fixes #5835

packages/tui/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed interactive sessions surviving terminal closure and entering a runaway render loop by stopping the TUI and raising SIGHUP when terminal input closes or output fails ([#5835](https://github.com/can1357/oh-my-pi/issues/5835)).
+
 ## [17.0.2] - 2026-07-17
 
 ### Added

packages/tui/README.md

@@ -522,7 +522,7 @@ The TUI works with any object implementing the `Terminal` interface:
 
 ```typescript
 interface Terminal {
-	start(onInput: (data: string) => void, onResize: () => void): void;
+	start(onInput: (data: string) => void, onResize: () => void, onDisconnect?: () => void): void;
 	stop(): void;
 	write(data: string): void;
 	get columns(): number;

packages/tui/src/terminal.ts

@@ -337,8 +337,8 @@ export function emergencyTerminalRestore(): void {
 /** Terminal-reported appearance (dark/light mode). */
 export type TerminalAppearance = "dark" | "light";
 export interface Terminal {
-	// Start the terminal with input and resize handlers
-	start(onInput: (data: string) => void, onResize: () => void): void;
+	// Start the terminal with input, resize, and host-disconnect handlers.
+	start(onInput: (data: string) => void, onResize: () => void, onDisconnect?: () => void): void;
 
 	// Stop the terminal and restore state
 	stop(): void;
@@ -483,6 +483,16 @@ export class ProcessTerminal implements Terminal {
 	#modifyOtherKeysTimeout?: Timer;
 	#stdinBuffer?: StdinBuffer;
 	#stdinDataHandler?: (data: string) => void;
+	#disconnectHandler?: () => void;
+	#stdinEndHandler = () => {
+		this.#markTerminalDisconnected("stdin ended");
+	};
+	#stdinCloseHandler = () => {
+		this.#markTerminalDisconnected("stdin closed");
+	};
+	#stdinErrorHandler = (err: Error) => {
+		this.#markTerminalDisconnected("stdin failed", err);
+	};
 	#dead = false;
 	// Captured at construction and re-read at start(): when true, every real
 	// terminal side effect (writes, probes, raw mode, SIGWINCH, timers) is
@@ -491,7 +501,7 @@ export class ProcessTerminal implements Terminal {
 	#writeLogPath = $env.PI_TUI_WRITE_LOG || "";
 	#stdoutErrorCleanup?: () => void;
 	#stdoutErrorHandler = (err: Error) => {
-		this.#markTerminalWriteFailed(err);
+		this.#markTerminalDisconnected("stdout failed", err);
 	};
 
 	#windowsVTInputRestore?: () => void;
@@ -577,9 +587,10 @@ export class ProcessTerminal implements Terminal {
 		this.#privateModeCallbacks.push(callback);
 	}
 
-	start(onInput: (data: string) => void, onResize: () => void): void {
+	start(onInput: (data: string) => void, onResize: () => void, onDisconnect?: () => void): void {
 		this.#inputHandler = onInput;
 		this.#resizeHandler = onResize;
+		this.#disconnectHandler = onDisconnect;
 
 		// Headless (tests): suppress every real-terminal side effect. Skip raw
 		// mode, stdin listeners, capability probes, SIGWINCH, and emergency-restore
@@ -604,6 +615,9 @@ export class ProcessTerminal implements Terminal {
 			process.stdin.setRawMode(true);
 		}
 		process.stdin.setEncoding("utf8");
+		process.stdin.on("end", this.#stdinEndHandler);
+		process.stdin.on("close", this.#stdinCloseHandler);
+		process.stdin.on("error", this.#stdinErrorHandler);
 		process.stdin.resume();
 
 		// Enable bracketed paste mode - terminal will wrap pastes in \x1b[200~ ... \x1b[201~
@@ -1425,6 +1439,10 @@ export class ProcessTerminal implements Terminal {
 			process.stdin.removeListener("data", this.#stdinDataHandler);
 			this.#stdinDataHandler = undefined;
 		}
+		process.stdin.removeListener("end", this.#stdinEndHandler);
+		process.stdin.removeListener("close", this.#stdinCloseHandler);
+		process.stdin.removeListener("error", this.#stdinErrorHandler);
+		this.#disconnectHandler = undefined;
 		this.#inputHandler = undefined;
 		this.#appearance = undefined;
 		if (this.#stdoutResizeListener) {
@@ -1450,10 +1468,26 @@ export class ProcessTerminal implements Terminal {
 		this.#stdoutErrorCleanup ??= registerStdoutErrorHandler(this.#stdoutErrorHandler);
 	}
 
-	#markTerminalWriteFailed(err: unknown): void {
+	#markTerminalDisconnected(reason: string, err?: unknown): void {
 		if (this.#dead) return;
 		this.#dead = true;
-		logger.warn("terminal write failed; disabling terminal rendering", { err });
+		logger.warn("terminal disconnected; stopping interactive rendering", { reason, err });
+
+		const disconnectHandler = this.#disconnectHandler;
+		this.#disconnectHandler = undefined;
+		if (!disconnectHandler) return;
+		disconnectHandler();
+
+		if (process.platform === "win32") {
+			void postmortem.quit(129);
+			return;
+		}
+		try {
+			process.kill(process.pid, "SIGHUP");
+		} catch (signalErr) {
+			logger.error("Failed to deliver terminal disconnect signal; exiting directly", { err: signalErr });
+			void postmortem.quit(129);
+		}
 	}
 
 	write(data: string): void {
@@ -1500,7 +1534,7 @@ export class ProcessTerminal implements Terminal {
 				process.stdout.write(data);
 			}
 		} catch (err) {
-			this.#markTerminalWriteFailed(err);
+			this.#markTerminalDisconnected("stdout failed", err);
 		}
 	}
 

packages/tui/src/tui.ts

@@ -1571,7 +1571,9 @@ export class TUI extends Container {
 				}
 				this.#armMultiplexerResizeTimer(false);
 			},
+			() => this.stop(),
 		);
+		if (this.#stopped) return;
 		for (const listener of this.#startListeners) {
 			try {
 				listener();

packages/tui/test/process-terminal-render-harness.ts

@@ -43,6 +43,8 @@ export interface ProcessTerminalRenderHarness {
 	readonly probe: WidthProbe;
 	/** Raw bytes the TUI wrote to stdout, in order. */
 	readonly writes: string[];
+	/** Signals the terminal requested from the host process, in order. */
+	readonly signals: Array<{ pid: number; signal: string | number | undefined }>;
 	/** Wait for the render scheduler to flush any pending paint. */
 	settle(): Promise<void>;
 	/** Simulate an OS resize (SIGWINCH / ConPTY): refresh stdout dims, fire `resize`. */
@@ -51,6 +53,10 @@ export interface ProcessTerminalRenderHarness {
 	inBand(rows: number, columns: number, yPixels?: number, xPixels?: number): Promise<void>;
 	/** Feed raw byte chunks through the real stdin pipeline (StdinBuffer reassembly included). */
 	feed(...chunks: string[]): Promise<void>;
+	/** End stdin as a terminal host does when its pane disappears. */
+	endInput(): Promise<void>;
+	/** Fail stdout as a revoked terminal descriptor does on write. */
+	failOutput(): Promise<void>;
 	dispose(): void;
 }
 
@@ -82,8 +88,12 @@ export function createProcessTerminalRenderHarness(
 	Object.defineProperty(process.stdout, "rows", { value: initialRows, configurable: true });
 
 	const writes: string[] = [];
+	const signals: Array<{ pid: number; signal: string | number | undefined }> = [];
 	const spies = [
-		vi.spyOn(process, "kill").mockReturnValue(true),
+		vi.spyOn(process, "kill").mockImplementation((pid, signal) => {
+			signals.push({ pid, signal });
+			return true;
+		}),
 		vi.spyOn(process.stdin, "resume").mockImplementation(() => process.stdin),
 		vi.spyOn(process.stdin, "pause").mockImplementation(() => process.stdin),
 		vi.spyOn(process.stdin, "setEncoding").mockImplementation(() => process.stdin),
@@ -112,6 +122,7 @@ export function createProcessTerminalRenderHarness(
 		tui,
 		probe,
 		writes,
+		signals,
 		settle,
 		async osResize(columns, rows) {
 			Object.defineProperty(process.stdout, "columns", { value: columns, configurable: true });
@@ -127,6 +138,14 @@ export function createProcessTerminalRenderHarness(
 			for (const chunk of chunks) process.stdin.emit("data", chunk);
 			await settle();
 		},
+		async endInput() {
+			process.stdin.emit("end");
+			await settle();
+		},
+		async failOutput() {
+			process.stdout.emit("error", new Error("terminal revoked"));
+			await settle();
+		},
 		dispose() {
 			tui.stop();
 			setTerminalHeadless(previousHeadless);

packages/tui/test/process-terminal-render.test.ts

@@ -88,4 +88,30 @@ describe("ProcessTerminal geometry reflow through the renderer", () => {
 		expect(harness.terminal.rows).toBe(30);
 		expect(harness.terminal.columns).toBe(100);
 	});
+
+	it("stops rendering and raises SIGHUP when terminal input ends", async () => {
+		harness = createProcessTerminalRenderHarness(100, 30);
+		await harness.settle();
+		const rendersBeforeDisconnect = harness.probe.widths.length;
+
+		await harness.endInput();
+		harness.tui.requestRender(true);
+		await harness.settle();
+
+		expect(harness.probe.widths).toHaveLength(rendersBeforeDisconnect);
+		expect(harness.signals.at(-1)).toEqual({ pid: process.pid, signal: "SIGHUP" });
+	});
+
+	it("stops rendering and raises SIGHUP when terminal output fails", async () => {
+		harness = createProcessTerminalRenderHarness(100, 30);
+		await harness.settle();
+		const rendersBeforeDisconnect = harness.probe.widths.length;
+
+		await harness.failOutput();
+		harness.tui.requestRender(true);
+		await harness.settle();
+
+		expect(harness.probe.widths).toHaveLength(rendersBeforeDisconnect);
+		expect(harness.signals.at(-1)).toEqual({ pid: process.pid, signal: "SIGHUP" });
+	});
 });