Get raw mode fulling working for bun.

src/bun/ffi.ts

@@ -1,8 +1,7 @@
-// Bun-specific ffi code
-import { dlopen, ptr, FFIType, suffix, toArrayBuffer } from "bun:ffi";
-import {STDIN_FILENO, TCSANOW} from "../common/ffi";
-
-const termiosArray = new Uint8Array(60);
+/**
+ * This is all the nasty ffi setup for the bun runtime
+ */
+import { dlopen, ptr, suffix } from "bun:ffi";
 
 const getLib = (name: string) => {
 	return dlopen(
@@ -29,26 +28,13 @@ let cStdLib = {symbols: {}};
 try {
 	cStdLib = getLib(`libc.${suffix}`);
 } catch {
-	cStdLib = getLib(`libc.${suffix}.6`);
-}
-
-export const enableRawMode = () => {
-	// Get the current termios settings
-	const termiosPtr = ptr(termiosArray);
-	cStdLib.symbols.tcgetattr(STDIN_FILENO, termiosPtr);
-
-	const oldTermios = new Uint8Array(toArrayBuffer(termiosPtr, 0, 60), 0, 60);
-	console.info(oldTermios);
-
-	// Update termios struct with raw settings
-	cStdLib.symbols.cfmakeraw(termiosPtr);
-
-	// Actually set the new termios settings
-	cStdLib.symbols.tcsetattr(STDIN_FILENO, TCSANOW, termiosPtr);
-
-	return () => {
-		const oldTermiosPtr = ptr(oldTermios);
-
-		cStdLib.symbols.tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
+	try {
+		cStdLib = getLib(`libc.${suffix}.6`);
+	}
+	catch {
+		throw new Error('Could not find c standard library');
 	}
 }
+
+export const { tcgetattr, tcsetattr, cfmakeraw } = cStdLib.symbols;
+export { ptr };

src/bun/index.ts

@@ -2,24 +2,25 @@
  * The main entrypoint when using Bun as the runtime
  */
 
-import {enableRawMode} from './ffi'
+import {Termios} from './termios'
 
 export async function main(): Promise<number> {
-	const disableRawMode = enableRawMode();
+	const t = new Termios();
+	t.enableRawMode();
 
 	const decoder = new TextDecoder();
 	for await (const chunk of Bun.stdin.stream()) {
 		const char = String(decoder.decode(chunk)).trim();
 
 		if (char === 'q') {
-			disableRawMode();
+			t.disableRawMode();
 			return 0;
 		}
 	}
 
 	process.on("exit", (code) => {
 		console.log(`Process exited with code ${code}`);
-		disableRawMode();
+		t.disableRawMode();
 	});
 
 	return -1;

src/bun/termios.ts

@@ -0,0 +1,81 @@
+import { STDIN_FILENO, TCSANOW, ITermios, TERMIOS_SIZE } from "../common/termios";
+import { cfmakeraw, tcgetattr, tcsetattr, ptr } from "./ffi";
+
+/**
+ * Implementation to toggle raw mode with Bun runtime
+ */
+export class Termios implements ITermios {
+	/**
+	 * Are we in raw mode?
+	 * @private
+	 */
+	#inRawMode:boolean;
+
+	/**
+	 * The saved version of the termios struct for cooked/canonical mode
+	 * @private
+	 */
+	#cookedTermios: Uint8Array;
+
+	/**
+	 * The data for the termios struct we are manipulating
+	 * @private
+	 */
+	#termios: Uint8Array;
+
+	/**
+	 * The pointer to the termios struct
+	 * @private		// this.#ptr = ptr(this.#termios);
+	 */
+	#ptr: any;
+
+	constructor() {
+		this.#inRawMode = false;
+
+		// These are the TypedArrays linked to the raw pointer data
+		this.#cookedTermios = new Uint8Array(TERMIOS_SIZE);
+		this.#termios = new Uint8Array(TERMIOS_SIZE);
+
+		// The current pointer for C
+		this.#ptr = ptr(this.#termios);
+	}
+
+	get inRawMode() {
+		return this.#inRawMode;
+	}
+
+	enableRawMode() {
+		if (this.#inRawMode) {
+			throw new Error('Can not enable raw mode when in raw mode');
+		}
+
+		// Get the current termios settings
+		tcgetattr(STDIN_FILENO, this.#ptr);
+
+		// The #ptr property is pointing to the #termios TypedArray. As the pointer
+		// is manipulated, the TypedArray is as well. We will use this to save
+		// the original canonical/cooked terminal settings for disabling raw mode later.
+		this.#cookedTermios = new Uint8Array(this.#termios, 0, 60);
+
+		// Update termios struct with raw settings
+		cfmakeraw(this.#ptr);
+
+		// Actually set the new termios settings
+		tcsetattr(STDIN_FILENO, TCSANOW, this.#ptr);
+		this.#inRawMode = true;
+	}
+
+	disableRawMode() {
+		// Don't even bother throwing an error if we try to disable raw mode
+		// and aren't in raw mode. It just doesn't really matter.
+		if (!this.#inRawMode) {
+			return;
+		}
+
+		const oldTermiosPtr = ptr(this.#cookedTermios);
+		tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
+
+		this.#inRawMode = false;
+	}
+}
+

src/common/ffi.ts

@@ -1,4 +0,0 @@
-export const STDIN_FILENO = 0;
-export const STOUT_FILENO = 1;
-export const TCSANOW = 0;
-export const TCSAFLUSH = 2;

src/common/termios.ts

@@ -0,0 +1,26 @@
+export const STDIN_FILENO = 0;
+export const STOUT_FILENO = 1;
+export const TCSANOW = 0;
+export const TCSAFLUSH = 2;
+
+export const TERMIOS_SIZE = 60;
+
+/**
+ * Common interface for setting Termios properties
+ */
+export interface ITermios {
+	/**
+	 * Are we currently in raw mode?
+	 */
+	inRawMode: boolean;
+
+	/**
+	 * Toggles on raw mode
+	 */
+	enableRawMode(): void;
+
+	/**
+	 * Restores canonical mode
+	 */
+	disableRawMode(): void;
+}

src/deno/termios.ts

@@ -2,6 +2,8 @@
 
 // Determine library extension based on
 // your OS.
+// import { termiosStruct } from "../common/termios.ts";
+
 let libSuffix = '';
 switch (Deno.build.os) {
 	case 'windows':