device/tty: Fix IGNCR and INLCR handling

Author: marv7000

kernel/src/device/input/mod.rs

@@ -501,7 +501,7 @@ fn key_byte(code: u16, state: &KeyboardState) -> Option<u8> {
         input::KEY_KPASTERISK => Some(b'*'),
         input::KEY_KPMINUS => Some(b'-'),
         input::KEY_KPPLUS => Some(b'+'),
-        input::KEY_KPENTER | input::KEY_ENTER => Some(b'\n'),
+        input::KEY_KPENTER | input::KEY_ENTER => Some(b'\r'),
         input::KEY_BACKSPACE => Some(0x7f),
         input::KEY_TAB => Some(b'\t'),
         input::KEY_ESC => Some(0x1b),
@@ -534,7 +534,7 @@ fn ctrl_key_byte(code: u16) -> Option<u8> {
         input::KEY_MINUS => Some(0x1f),
         input::KEY_2 => Some(0x00),
         input::KEY_8 => Some(0x7f),
-        input::KEY_KPENTER | input::KEY_ENTER => Some(b'\n'),
+        input::KEY_KPENTER | input::KEY_ENTER => Some(b'\r'),
         input::KEY_BACKSPACE => Some(0x7f),
         input::KEY_TAB => Some(b'\t'),
         input::KEY_ESC => Some(0x1b),

kernel/src/device/tty/mod.rs

@@ -77,6 +77,14 @@ impl LineDiscipline {
         self.termios.c_iflag & ICRNL != 0
     }
 
+    fn is_igncr(&self) -> bool {
+        self.termios.c_iflag & IGNCR != 0
+    }
+
+    fn is_inlcr(&self) -> bool {
+        self.termios.c_iflag & INLCR != 0
+    }
+
     fn cc(&self, idx: u32) -> u8 {
         self.termios.c_cc[idx as usize]
     }
@@ -98,8 +106,17 @@ impl LineDiscipline {
 
     pub fn input_char(&mut self, mut byte: u8, tty: &Tty) -> Vec<u8> {
         let mut output = Vec::new();
-        if self.is_icrnl() && byte == b'\r' {
-            byte = b'\n';
+
+        // CR/NL input translation.
+        if byte == b'\r' {
+            if self.is_igncr() {
+                return output;
+            }
+            if self.is_icrnl() {
+                byte = b'\n';
+            }
+        } else if byte == b'\n' && self.is_inlcr() {
+            byte = b'\r';
         }
 
         // Signal generation.