add key event parser; handles basic ascii and ctrl/alt combinations

examples/print.rs

@@ -1,21 +1,17 @@
-use ants::{event::Events, raw_mode};
+use ants::{
-use std::{
+	event::{Event, Events, Key, Mod},
-	io::{stdin, Read},
+	raw_mode,
-	time::{Duration, SystemTime},
 };
 
 fn main() {
 	raw_mode::enter().unwrap();
-
+	print!("Press Ctrl+q to exit.\r\n");
-	let start_time = SystemTime::now();
+	let mut events = Events::new();
-
+	loop {
-	let mut buf = Vec::new();
+		if let Some(event) = events.next() {
-	while start_time.elapsed().unwrap() < Duration::from_secs(5) {
+			print!("{:?}\r\n", event);
-		let mut b = [0u8];
+			if let Event::Key(Key::Char('q'), Mod::Ctrl) = event {
-		if let Ok(_n) = stdin().read(&mut b) {
+				break;
-			if b[0] != 0 {
-				buf.push(b[0]);
-				print!("[{}]:{}\n\r", b[0], String::from_utf8_lossy(&buf));
 			}
 		}
 	}

src/event.rs

@@ -1,11 +1,112 @@
-use std::io::{stdin, Stdin};
+use std::io::{stdin, Read, Stdin};
+
+const BS: u8 = 8;
+const ESC: u8 = 27;
+const TAB: u8 = b'\t';
+const LF: u8 = b'\n';
+const CR: u8 = b'\r';
+const DEL: u8 = 127;
+
+#[derive(Debug)]
+pub enum Event {
+	Key(Key, Mod),
+	Unsupported(Vec<u8>),
+	// may add mouse events at some point
+}
+
+#[derive(Debug)]
+pub enum Mod {
+	None,
+	Shift,
+	Ctrl,
+	Alt,
+	/// only works for some specific keys
+	ShiftCtrl,
+	/// only works for some specific keys
+	ShiftAlt,
+	/// only works for some specific keys
+	CtrlAlt,
+	/// only works for some specific keys
+	ShiftCtrlAlt,
+}
+
+#[non_exhaustive]
+#[derive(Debug)]
+pub enum Key {
+	Char(char),
+	Right,
+	Left,
+	Up,
+	Down,
+	Home,
+	End,
+	PageUp,
+	PageDown,
+	/// also Ctrl+H
+	Backspace,
+	Delete,
+	/// also Ctrl+[
+	Escape,
+	/// \r or \n or Ctrl+M or Ctrl+J
+	Enter,
+	/// \t or Ctrl+I
+	Tab,
+	F(u8),
+}
 
 pub struct Events {
-	bytes: Stdin,
+	source: Stdin,
+	buffer: Vec<u8>,
 }
 
 impl Events {
 	pub fn new() -> Self {
-		Self { bytes: stdin() }
+		Self {
+			source: stdin(),
+			buffer: Vec::new(),
+		}
+	}
+
+	fn parse_esc(&mut self) -> Event {
+		if self.buffer.is_empty() {
+			return Event::Key(Key::Escape, Mod::None);
+		}
+
+		let byte = self.buffer[0];
+		self.buffer = self.buffer[1..].to_vec();
+		match byte {
+			ESC => Event::Key(Key::Escape, Mod::None),
+			BS => Event::Key(Key::Backspace, Mod::Alt),
+			DEL => Event::Key(Key::Delete, Mod::Alt),
+			LF | CR => Event::Key(Key::Enter, Mod::Alt),
+			TAB => Event::Key(Key::Tab, Mod::Alt),
+			c @ 1..=26 => Event::Key(Key::Char((c + 96).into()), Mod::CtrlAlt), // ctrl + letter
+			c @ b' '..=b'~' => Event::Key(Key::Char(c.into()), Mod::Alt),       // regular ascii charaters
+			_ => Event::Unsupported(vec![ESC, byte]),
+		}
+	}
+}
+
+impl Iterator for Events {
+	type Item = Event;
+
+	fn next(&mut self) -> Option<Self::Item> {
+		self.source.read_to_end(&mut self.buffer).ok()?;
+		if self.buffer.is_empty() {
+			return None;
+		}
+
+		let byte = self.buffer[0];
+		self.buffer = self.buffer[1..].to_vec();
+		Some(match byte {
+			ESC => self.parse_esc(),
+			BS => Event::Key(Key::Backspace, Mod::None),
+			DEL => Event::Key(Key::Delete, Mod::None),
+			LF | CR => Event::Key(Key::Enter, Mod::None),
+			TAB => Event::Key(Key::Tab, Mod::None),
+			c @ 1..=26 => Event::Key(Key::Char((c + 96).into()), Mod::Ctrl), // ctrl + letter
+			c @ b' '..=b'~' => Event::Key(Key::Char(c.into()), Mod::None),   // regular ascii charaters
+			_ => Event::Unsupported(vec![byte]),
+		})
 	}
 }

src/raw_mode.rs

@@ -1,12 +1,13 @@
+#![allow(unused)]
 use std::{
 	ffi::{c_char, c_int, c_uint},
-	io::{self, Result},
+	io,
 	os::fd::{self, AsFd},
 };
 
 static mut PREV_TERMINAL_STATE: Option<Termios> = None;
 
-pub fn enter() -> Result<()> {
+pub fn enter() -> io::Result<()> {
 	if unsafe { PREV_TERMINAL_STATE.is_some() } {
 		return Ok(());
 	}
@@ -20,20 +21,22 @@ pub fn enter() -> Result<()> {
 		PREV_TERMINAL_STATE = Some(state.clone());
 	}
 	// https://man7.org/linux/man-pages/man3/termios.3.html
-	// termios.c_iflag &= !(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
+	state.c_iflag &= !(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
-	// termios.c_oflag &= !OPOST;
+	state.c_oflag &= !OPOST;
-	// termios.c_lflag &= !(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+	state.c_lflag &= !(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
-	// termios.c_cflag &= !(CSIZE | PARENB);
+	state.c_cflag &= !(CSIZE | PARENB);
-	// termios.c_cflag |= CS8;
+	state.c_cflag |= CS8;
+	state.c_cc[VMIN] = 0; // minimum bytes read before read() returns
+	state.c_cc[VTIME] = 0; // timeout in 100ms increments (set to none)
 	unsafe {
 		// set to raw mode
-		cfmakeraw(&state);
+		// cfmakeraw(&state);
 		check_err(tcsetattr(stdin.as_fd(), 0, &state))?;
 	}
 	Ok(())
 }
 
-pub fn exit() -> Result<()> {
+pub fn exit() -> io::Result<()> {
 	unsafe {
 		if let Some(termios) = PREV_TERMINAL_STATE.as_ref() {
 			let stdin = io::stdin();
@@ -43,7 +46,7 @@ pub fn exit() -> Result<()> {
 	Ok(())
 }
 
-fn check_err(val: c_int) -> Result<()> {
+fn check_err(val: c_int) -> io::Result<()> {
 	if val == -1 {
 		Err(io::Error::last_os_error())
 	} else {
@@ -61,8 +64,8 @@ struct Termios {
 	pub c_line: c_char,
 	pub c_cc: [c_char; 32],
 	// these two seem to be platform specific and don't need to be used
-	// pub c_ispeed: c_int,
+	pub c_ispeed: c_int,
-	// pub c_ospeed: c_int,
+	pub c_ospeed: c_int,
 }
 
 #[link(name = "c")]
@@ -74,7 +77,7 @@ extern "C" {
 	/// set terminal flags to raw mode
 	fn cfmakeraw(termios_p: *const Termios);
 }
-/*
+//*
 const TCIOFF: c_int = 2;
 const TCION: c_int = 3;
 const TCOOFF: c_int = 0;
@@ -115,6 +118,25 @@ const ONLRET: c_uint = 0o000040;
 const OFILL: c_uint = 0o000100;
 const OFDEL: c_uint = 0o000200;
 
+const SIGSTKSZ: usize = 8192;
+const MINSIGSTKSZ: usize = 2048;
+const CBAUD: c_uint = 0o0010017;
+const TAB1: c_int = 0x00000800;
+const TAB2: c_int = 0x00001000;
+const TAB3: c_int = 0x00001800;
+const CR1: c_int = 0x00000200;
+const CR2: c_int = 0x00000400;
+const CR3: c_int = 0x00000600;
+const FF1: c_int = 0x00008000;
+const BS1: c_int = 0x00002000;
+const VT1: c_int = 0x00004000;
+const VWERASE: usize = 14;
+const VREPRINT: usize = 12;
+const VSUSP: usize = 10;
+const VSTART: usize = 8;
+const VSTOP: usize = 9;
+const VDISCARD: usize = 13;
+const VTIME: usize = 5;
 const IXON: c_uint = 0x00000400;
 const IXOFF: c_uint = 0x00001000;
 const ONLCR: c_uint = 0x4;