term: add scrollback

kernel/src/arch/x86/peripherals/ps2/codeset.rs

@@ -134,15 +134,15 @@ table! {
     pub static CODE_SET_1_E0: [Key; 128; Key::Unknown] = [
         0x1D => Key::RControl,
         0x38 => Key::RAlt,
-        // 0x47 => Key::Home,
-        // 0x48 => Key::Up,
-        // 0x49 => Key::PageUp,
-        // 0x4B => Key::Left,
-        // 0x4D => Key::Right,
-        // 0x4F => Key::End,
-        // 0x50 => Key::Down,
-        // 0x51 => Key::PageDown,
-        // 0x52 => Key::Insert,
-        // 0x53 => Key::Delete,
+        0x47 => Key::Home,
+        0x48 => Key::Up,
+        0x49 => Key::PageUp,
+        0x4B => Key::Left,
+        0x4D => Key::Right,
+        0x4F => Key::End,
+        0x50 => Key::Down,
+        0x51 => Key::PageDown,
+        0x52 => Key::Insert,
+        0x53 => Key::Delete,
     ];
 }

kernel/src/arch/x86/peripherals/ps2/mod.rs

@@ -79,6 +79,7 @@ impl InterruptHandler for PS2Controller {
     fn handle_irq(self: Arc<Self>, _vector: IrqVector) -> bool {
         let mut count = 0;
         let mut inner = self.inner.lock();
+        let mut e0 = false;
 
         loop {
             let Some(mut scancode) = inner.try_recv() else {
@@ -87,7 +88,10 @@ impl InterruptHandler for PS2Controller {
 
             count += 1;
 
-            let e0 = scancode == 0xE0;
+            if scancode == 0xE0 {
+                e0 = true;
+                continue;
+            }
             let release = scancode >= 0x80;
 
             if release {
@@ -101,6 +105,8 @@ impl InterruptHandler for PS2Controller {
                 KeyboardKeyEvent::Pressed(key)
             };
 
+            e0 = false;
+
             ygg_driver_input::send_event(event);
         }
 

lib/abi/src/io/input.rs

@@ -12,12 +12,22 @@ pub enum KeyboardKey {
     RShift,
     LControl,
     RControl,
+    PageUp,
+    PageDown,
     LAlt,
     RAlt,
     CapsLock,
     Escape,
     Backspace,
     Tab,
+    Up,
+    Down,
+    Left,
+    Right,
+    Home,
+    End,
+    Insert,
+    Delete,
     Unknown,
 }
 
@@ -54,6 +64,16 @@ impl KeyboardKey {
         // 0x98: Escape
         // 0x99: Backspace
         // 0x9A: Tab
+        // 0xA0: PageUp
+        // 0xA1: PageDown
+        // 0xA2: Up
+        // 0xA3: Down
+        // 0xA4: Left
+        // 0xA5: Right
+        // 0xA6: Home
+        // 0xA7: End
+        // 0xA8: Insert
+        // 0xA9: Delete
         // 0xFF: Unknown
         KeyboardKeyCode(match self {
             Self::Char(b) => b as u16,
@@ -69,6 +89,16 @@ impl KeyboardKey {
             Self::Escape => 0x98,
             Self::Backspace => 0x99,
             Self::Tab => 0x9A,
+            Self::PageUp => 0xA0,
+            Self::PageDown => 0xA1,
+            Self::Up => 0xA2,
+            Self::Down => 0xA3,
+            Self::Left => 0xA4,
+            Self::Right => 0xA5,
+            Self::Home => 0xA6,
+            Self::End => 0xA7,
+            Self::Insert => 0xA8,
+            Self::Delete => 0xA9,
             Self::Unknown => 0xFF,
         })
     }
@@ -93,6 +123,16 @@ impl KeyboardKey {
                 0x98 => Self::Escape,
                 0x99 => Self::Backspace,
                 0x9A => Self::Tab,
+                0xA0 => Self::PageUp,
+                0xA1 => Self::PageDown,
+                0xA2 => Self::Up,
+                0xA3 => Self::Down,
+                0xA4 => Self::Left,
+                0xA5 => Self::Right,
+                0xA6 => Self::Home,
+                0xA7 => Self::End,
+                0xA8 => Self::Insert,
+                0xA9 => Self::Delete,
                 _ => Self::Unknown,
             }
         }

userspace/term/src/main.rs

@@ -85,12 +85,15 @@ impl DrawState {
             dt.fill(default_bg);
         }
 
+
         if cursor_dirty {
             state.buffer.set_row_dirty(self.old_cursor.row);
         }
 
         let bytes_per_line = (self.font.width() as usize + 7) / 8;
-        for (i, row) in state.buffer.dirty_rows() {
+        let scroll = state.adjust_scroll();
+        let cursor_visible = scroll == 0;
+        state.buffer.visible_rows_mut(scroll, |i, row| {
             let cy = i * fh;
 
             for (j, cell) in row.cells().enumerate() {
@@ -132,9 +135,12 @@ impl DrawState {
                     y += 1;
                 }
             }
-        }
+        });
+        // for (i, row) in state.buffer.dirty_rows() {
+        // }
 
         // TODO check if there's a character under cursor
+        if cursor_visible {
             let cx = state.cursor.col * fw;
             let cy = state.cursor.row * fh;
 
@@ -153,6 +159,8 @@ impl DrawState {
             }
 
             self.old_cursor = state.cursor;
+        }
+
         self.force_redraw = false;
         self.focus_changed = false;
     }
@@ -211,32 +219,56 @@ impl Terminal<'_> {
             EventOutcome::Redraw
         });
 
+        let state_c = state.clone();
         let pty_master_c = pty_master.clone();
         window.set_on_key_input(move |ev| {
+            let mut s = state_c.lock().unwrap();
             let mut pty_master = pty_master_c.lock().unwrap();
+            let mut need_redraw = false;
 
             // TODO error reporting from handlers
             if let Some(input) = ev.input {
                 pty_master.write_all(&[input as u8]).unwrap();
+                need_redraw = s.scroll_end();
             } else {
                 match (ev.modifiers, ev.key) {
                     (KeyModifiers::NONE, KeyboardKey::Escape) => {
                         pty_master.write_all(b"\x1B").unwrap();
+                        need_redraw = s.scroll_end();
                     }
                     (KeyModifiers::NONE, KeyboardKey::Backspace) => {
                         pty_master.write_all(&[termios.chars.erase]).unwrap();
+                        need_redraw = s.scroll_end();
                     }
                     (KeyModifiers::CTRL, KeyboardKey::Char(b'c')) => {
                         pty_master.write_all(&[termios.chars.interrupt]).unwrap();
+                        need_redraw = s.scroll_end();
                     }
                     (KeyModifiers::CTRL, KeyboardKey::Char(b'd')) => {
                         pty_master.write_all(&[termios.chars.eof]).unwrap();
+                        need_redraw = s.scroll_end();
+                    }
+                    (KeyModifiers::SHIFT, KeyboardKey::PageUp) => {
+                        need_redraw = s.scroll_up();
+                    }
+                    (KeyModifiers::SHIFT, KeyboardKey::PageDown) => {
+                        need_redraw = s.scroll_down();
+                    }
+                    (KeyModifiers::SHIFT, KeyboardKey::Home) => {
+                        need_redraw = s.scroll_home();
+                    }
+                    (KeyModifiers::SHIFT, KeyboardKey::End) => {
+                        need_redraw = s.scroll_end();
                     }
                     _ => (),
                 }
             }
 
+            if need_redraw {
+                EventOutcome::Redraw
+            } else {
                 EventOutcome::None
+            }
         });
 
         let draw_state_c = draw_state.clone();

userspace/term/src/state.rs

@@ -1,3 +1,5 @@
+use std::collections::VecDeque;
+
 use crate::attr::{CellAttributes, Color};
 
 #[derive(Clone, Copy, Debug)]
@@ -13,9 +15,11 @@ pub struct GridRow {
 }
 
 pub struct Buffer {
+    scrollback: VecDeque<GridRow>,
     rows: Vec<GridRow>,
     width: usize,
     height: usize,
+    scrollback_limit: usize,
 }
 
 #[derive(Clone, Copy, PartialEq, Eq)]
@@ -36,6 +40,7 @@ pub struct State {
     esc_state: EscapeState,
     esc_args: Vec<u32>,
 
+    scroll: usize,
     pub cursor: Cursor,
     #[allow(unused)]
     saved_cursor: Option<Cursor>,
@@ -106,6 +111,8 @@ impl Buffer {
     pub fn new(width: usize, height: usize, bg: Color) -> Self {
         Self {
             rows: vec![GridRow::new(width, bg); height],
+            scrollback: VecDeque::new(),
+            scrollback_limit: 1024,
             width,
             height,
         }
@@ -115,15 +122,30 @@ impl Buffer {
         self.rows.fill(GridRow::new(self.width, bg));
     }
 
-    pub fn dirty_rows(&mut self) -> impl Iterator<Item = (usize, &mut GridRow)> {
-        self.rows.iter_mut().enumerate().filter_map(|(i, row)| {
+    pub fn iter_rows_mut<F: FnMut(usize, &mut GridRow)>(&mut self, scroll: usize, mut handler: F) {
+        let scroll = scroll.min(self.scrollback.len());
+        let non_scroll = self.height.saturating_sub(scroll);
+        let scroll_end = self.height - non_scroll;
+
+        for y in 0..scroll_end {
+            let i = scroll - 1 - y;
+            let row = &mut self.scrollback[i];
+            handler(y, row);
+        }
+        for i in 0..non_scroll {
+            let y = scroll + i;
+            let row = &mut self.rows[i];
+            handler(y, row);
+        }
+    }
+
+    pub fn visible_rows_mut<F: FnMut(usize, &mut GridRow)>(&mut self, scroll: usize, mut handler: F) {
+        self.iter_rows_mut(scroll, |y, row| {
             if row.dirty {
                 row.dirty = false;
-                Some((i, row))
-            } else {
-                None
+                handler(y, row);
             }
-        })
+        });
     }
 
     pub fn resize(&mut self, width: usize, height: usize, bg: Color) {
@@ -142,6 +164,11 @@ impl Buffer {
     }
 
     pub fn scroll_once(&mut self, bg: Color) {
+        self.scrollback.push_front(self.rows[0].clone());
+        if self.scrollback.len() >= self.scrollback_limit {
+            self.scrollback.pop_back();
+        }
+
         for i in 1..self.height {
             self.rows[i - 1] = self.rows[i].clone();
             self.rows[i - 1].dirty = true;
@@ -156,6 +183,10 @@ impl Buffer {
     pub fn set_row_dirty(&mut self, row: usize) {
         self.rows[row].dirty = true;
     }
+
+    pub fn invalidate_rows(&mut self, scroll: usize) {
+        self.iter_rows_mut(scroll, |_, row| row.dirty = true);
+    }
 }
 
 impl State {
@@ -173,6 +204,7 @@ impl State {
             esc_state: EscapeState::Normal,
 
             cursor: Cursor { row: 0, col: 0 },
+            scroll: 0,
             saved_cursor: None,
 
             default_attributes,
@@ -183,6 +215,7 @@ impl State {
     pub fn resize(&mut self, width: usize, height: usize) {
         self.buffer
             .resize(width, height, self.default_attributes.bg);
+        self.scroll = 0;
 
         if self.cursor.row >= height {
             self.cursor.row = height - 1;
@@ -370,4 +403,63 @@ impl State {
             EscapeState::Csi => self.handle_ctlseq_byte(ch),
         }
     }
+
+    pub fn invalidate_current_viewport(&mut self) {
+        self.buffer.invalidate_rows(self.scroll);
+    }
+
+    pub fn adjust_scroll(&mut self) -> usize {
+        if self.scroll > self.buffer.scrollback.len() {
+            self.scroll = self.buffer.scrollback.len();
+        }
+
+        self.scroll
+    }
+
+    pub fn scroll_up(&mut self) -> bool {
+        let max = self.buffer.scrollback.len();
+        if max == 0 {
+            self.scroll = 0;
+            return true;
+        }
+        let amount = max.min(8);
+        if amount != 0 {
+            self.scroll += amount;
+            self.invalidate_current_viewport();
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn scroll_down(&mut self) -> bool {
+        let amount = self.scroll.min(8);
+        if amount != 0 {
+            self.scroll -= amount;
+            self.invalidate_current_viewport();
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn scroll_home(&mut self) -> bool {
+        if self.scroll != self.buffer.scrollback.len() {
+            self.scroll = self.buffer.scrollback.len();
+            self.invalidate_current_viewport();
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn scroll_end(&mut self) -> bool {
+        if self.scroll != 0 {
+            self.scroll = 0;
+            self.invalidate_current_viewport();
+            true
+        } else {
+            false
+        }
+    }
 }