Supressed clippy errors and add some rust docs

kernel/src/graphics/ascii.rs

@@ -0,0 +1,236 @@
+/* use core::fmt;
+use spin::{Lazy, Mutex};
+use x86_64::instructions::interrupts;
+
+use super::framebuffer::{colour::Colour, display::FRAMEBUFFER_WRITER};
+
+// use crate::resources::font::{FONT_SPLEEN_8X16, Font};
+
+static FONT_WIDTH: u32 = 8;
+static FONT_HEIGHT: u32 = 16;
+
+pub static WRITER: Lazy<Mutex<Writer>> = Lazy::new(|| Mutex::new(Writer::new()));
+
+pub fn screensize_chars() -> (u32, u32) {
+    let writer = WRITER.lock();
+    (writer.screen_width, writer.screen_height)
+}
+
+pub struct Writer {
+    font: &'static Font,
+    /// Measured in chars not pixels.
+    screen_width: u32,
+    /// Measured in chars not pixels.
+    screen_height: u32,
+    /// 16 pixels tall.
+    text_line: u32,
+    /// 8 pixels wide.
+    text_col: u32,
+
+    fg_color: Colour,
+    bg_color: Colour,
+}
+
+impl Default for Writer {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Writer {
+    pub fn new() -> Self {
+        FRAMEBUFFER_WRITER.lock().as_mut().map_or_else(
+            || {
+                panic!("Framebuffer writer not initialized.");
+            },
+            |writer| Self {
+                font: &FONT_SPLEEN_8X16,
+                screen_width: writer.width() / 8,
+                screen_height: writer.height() / 16,
+                text_line: 0,
+                text_col: 0,
+                fg_color: Colour::White,
+                bg_color: Colour::Black,
+            },
+        )
+    }
+
+    pub const fn set_font(&mut self, font: &'static Font) {
+        self.font = font;
+    }
+
+    /// This is sent when the user types a backspace.
+    const BACKSPACE: u8 = 8;
+
+    pub fn write_glyph(&mut self, c: u8) {
+        if c == b'\n' {
+            self.newline();
+            return;
+        } else if c == Self::BACKSPACE {
+            self.backspace();
+            return;
+        }
+
+        // Get the character data from the font array. -- each byte is a row of pixels
+        let data: &[u8] = self.font.glyph_for(c as u16);
+
+        if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+            for (row, line) in data.iter().enumerate().take(16) {
+                for col in 0..8 {
+                    let pixel_x: u32 = self.text_col * FONT_WIDTH + col;
+                    let pixel_y: u32 = self.text_line * FONT_HEIGHT + row as u32;
+
+                    if line & (0x80 >> col) != 0 {
+                        // Write the foreground color
+                        writer.write_pixel(pixel_x as usize, pixel_y as usize, self.fg_color);
+                    } else {
+                        // Write the background color
+                        writer.write_pixel(pixel_x as usize, pixel_y as usize, self.bg_color);
+                    }
+                }
+            }
+        }
+
+        // Go to next position
+        if self.text_col + 1 >= self.screen_width {
+            self.newline();
+        } else {
+            self.text_col += 1;
+        }
+    }
+
+    pub const fn dimensions(&self) -> (u32, u32) {
+        (self.screen_width, self.screen_height)
+    }
+
+    pub const fn next_char(&mut self) {
+        self.text_col += 1;
+    }
+
+    pub const fn newline(&mut self) {
+        self.text_col = 0;
+
+        if self.text_line + 1 >= self.screen_height {
+            self.text_line = 0;
+        } else {
+            self.text_line += 1;
+        }
+    }
+
+    /// Handles the backspace character. TODO: Implement VT-100 style terminal control
+    /// codes alongside a shell. Not simple.
+    pub fn backspace(&mut self) {
+        if self.text_col > 0 {
+            self.text_col -= 1;
+            // Blank out the previous char.
+            self.write_glyph(b' ');
+            self.text_col -= 1;
+        }
+    }
+
+    pub fn write_string(&mut self, s: &str) {
+        for c in s.chars() {
+            self.write_glyph(c as u8);
+        }
+    }
+
+    pub const fn set_colour(&mut self, fg: Colour, bg: Colour) {
+        self.fg_color = fg;
+        self.bg_color = bg;
+    }
+
+    pub const fn reset_colour(&mut self) {
+        self.fg_color = Colour::White;
+        self.bg_color = Colour::Black;
+    }
+}
+
+impl core::fmt::Write for Writer {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        self.write_string(s);
+        Ok(())
+    }
+}
+
+fn write(args: fmt::Arguments, fg: Colour, bg: Colour) {
+    use core::fmt::Write;
+
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.set_colour(fg, bg);
+        writer.write_fmt(args).unwrap();
+        writer.reset_colour();
+    });
+}
+
+pub fn _print(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::White, Colour::Black);
+    })
+}
+
+pub fn _print_err(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::Red, Colour::Black);
+    })
+}
+
+pub fn _print_log(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::Yellow, Colour::Black);
+    })
+}
+
+pub fn clear_screen() {
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.text_line = 0;
+        writer.text_col = 0;
+
+        if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+            writer.clear();
+        }
+    });
+}
+
+pub fn reset_cursor() {
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.text_line = 0;
+        writer.text_col = 0;
+    });
+}
+
+#[macro_export]
+macro_rules! println_log {
+    () => ($crate::print_log!("\n"));
+    ($($arg:tt)*) => ($crate::print_log!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! print_log {
+    ($($arg:tt)*) => ($crate::_print_log(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::_print(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! printlnerr {
+    () => ($crate::printerr!("\n"));
+    ($($arg:tt)*) => ($crate::printerr!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! printerr {
+    ($($arg:tt)*) => ($crate::_print_err(format_args!($($arg)*)));
+}
+ */

kernel/src/graphics/colour.rs

@@ -0,0 +1,64 @@
+#[repr(u32)]
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+// Some predefined colours as well as custom colours in the proper format. This
+// assumes that the framebuffer uses 32bpp, something which we will assert on
+// initialisation.
+pub enum Colour {
+    Argb(u8, u8, u8, u8),
+    Rgb(u8, u8, u8),
+    HexARGB(u32),
+    Black = 0x000000FF,
+    Blue = 0x0000FFFF,
+    Green = 0x00FF00FF,
+    Cyan = 0x00FFFFFF,
+    Red = 0xFF0000FF,
+    Magenta = 0xFF00FFFF,
+    Yellow = 0xFFFF00FF,
+    White = 0xFFFFFFFF,
+}
+
+#[expect(
+    clippy::use_self,
+    reason = "Self is uglier and more verbose than `u32`"
+)]
+impl From<Colour> for u32 {
+    fn from(val: Colour) -> Self {
+        match val {
+            Colour::Argb(a, r, g, b) => {
+                (a as u32) << 24 | (r as u32) << 16 | (g as u32) << 8 | (b as u32)
+            }
+            Colour::Rgb(r, g, b) => {
+                ((r as u32) << 16) | (g as u32) << 8 | (b as u32)
+            }
+            Colour::HexARGB(hex) => hex,
+            Colour::Black => 0xFF000000,
+            Colour::Blue => 0xFF0000FF,
+            Colour::Green => 0xFF00FF00,
+            Colour::Cyan => 0xFF00FFFF,
+            Colour::Red => 0xFFFF0000,
+            Colour::Magenta => 0xFFFF00FF,
+            Colour::Yellow => 0xFFFFFF00,
+            Colour::White => 0xFFFFFFFF,
+        }
+    }
+}
+
+impl core::fmt::Display for Colour {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        match self {
+            Self::Argb(r, g, b, a) => {
+                write!(f, "RGBA(#{:x}{:x}{:x}{:x})", r, g, b, a)
+            }
+            Self::Rgb(r, g, b) => write!(f, "RGB(#{:x}{:x}{:x})", r, g, b),
+            Self::HexARGB(hex) => write!(f, "Hex(#{:x})", hex),
+            Self::Black => write!(f, "Black"),
+            Self::Blue => write!(f, "Blue"),
+            Self::Green => write!(f, "Green"),
+            Self::Cyan => write!(f, "Cyan"),
+            Self::Red => write!(f, "Red"),
+            Self::Magenta => write!(f, "Magenta"),
+            Self::Yellow => write!(f, "Yellow"),
+            Self::White => write!(f, "White"),
+        }
+    }
+}

kernel/src/graphics/font.rs

@@ -0,0 +1,46 @@
+#![allow(unused)]
+use libm::include_font;
+
+pub const FONT_SPLEEN_8X16: Font =
+    Font::new(include_font!("../../resources/font/spleen-8x16.psf"));
+
+pub const FONT_CP850_8X16: Font =
+    Font::new(include_font!("../../resources/font/cp850-8x16.psf"));
+
+pub struct Font {
+    width: usize,
+    height: usize,
+    length: u16,
+    data: [[u8; 16]; 512],
+}
+
+impl Font {
+    pub const fn new(data: [[u8; 16]; 512]) -> Self {
+        Self {
+            width: 8,
+            height: 16,
+            length: data.len() as u16,
+            data,
+        }
+    }
+
+    pub const fn glyph_for(&self, c: u16) -> &[u8] {
+        if c > self.length {
+            return &self.data[0];
+        }
+
+        &self.data[c as usize]
+    }
+
+    pub const fn width(&self) -> usize {
+        self.width
+    }
+
+    pub const fn height(&self) -> usize {
+        self.height
+    }
+
+    pub const fn default() -> &'static Self {
+        &FONT_SPLEEN_8X16
+    }
+}

kernel/src/graphics/framebuffer.rs

@@ -1 +1,158 @@
-//! Handles
+//! Handles setting up the framebuffer passed to us by Limine.
+#![expect(unused)]
+use crate::DEFAULT_FONT;
+
+use super::{colour::Colour, font::Font};
+
+use limine::framebuffer::Framebuffer;
+use limine::request::FramebufferRequest;
+use spin::{Lazy, Mutex};
+
+#[used]
+#[unsafe(link_section = ".requests")]
+/// The Limine framebuffer request.
+static FRAMEBUFFER_REQUEST: FramebufferRequest = FramebufferRequest::new();
+
+/// A mutex used for writing to the framebuffer, in most cases we can abstract
+/// this behind calls to println! etc.
+pub static FRAMEBUFFER_WRITER: Lazy<Mutex<Option<FramebufferWriter>>> = Lazy::new(
+    || {
+        Mutex::new(FRAMEBUFFER_REQUEST.get_response().map_or_else(
+            || {
+                unreachable!("Framebuffer request failed, got None.");
+            },
+            |framebuffer_response| {
+                let framebuffer =
+                    framebuffer_response.framebuffers().next()
+                    .expect("Expected to find at least one framebuffer in response, got zero.");
+                Some(FramebufferWriter::new(framebuffer, Colour::Black))
+            },
+        ))
+    },
+);
+
+/// The updated writer stores necessary fields from the [Framebuffer].
+/// This ensures that the contained types are Send, as Framebuffer was
+/// not marked as Send.
+///
+/// It also avoids the requirement for lifetimes.
+///
+/// Note this does not implement Writer as these functions only handle drawing
+/// pixels.
+pub struct FramebufferWriter {
+    pitch: u64,
+    /// Number of bits used per pixel, we expect 32 so this will be asserted
+    /// when we initialise the framebuffer.
+    bpp: u16,
+    /// A raw pointer to the framebuffer.
+    addr: *mut u8,
+    /// The width of the screen in pixels.
+    width: u64,
+    /// The height of the screen in pixels.
+    height: u64,
+    /// The default background colour of the Framebuffer.
+    background_colour: Colour,
+}
+
+/// Marker trait required for sending the writer across threads, which will
+/// probably come in handy later.
+unsafe impl Send for FramebufferWriter {}
+/// Marker trait required for sharing the writer across threads, which will
+/// probably come in handy later.
+///
+/// # Note
+///
+/// We wrap this in a Mutex later so this should handle synchronising accesses.
+unsafe impl Sync for FramebufferWriter {}
+
+impl FramebufferWriter {
+    /// Creates a new [`FramebufferWriter`] with the specified background
+    /// colour.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the bits per pixel for the framebuffer is not 32 bits per
+    /// pixel, because we didn't exactly handle other cases.
+    pub fn new(framebuffer: Framebuffer, background_colour: Colour) -> Self {
+        // We don't handle other cases, this should not trigger on most newer
+        // hardware.
+        assert!(framebuffer.bpp() == 32);
+
+        Self {
+            pitch: framebuffer.pitch(),
+            bpp: framebuffer.bpp(),
+            addr: framebuffer.addr(),
+            width: framebuffer.width(),
+            height: framebuffer.height(),
+            background_colour,
+        }
+    }
+
+    /// Writes a pixel with `colour` to the screen at the given `(x, y)`
+    /// coordinates (in pixels).
+    pub fn write_pixel(&self, x: usize, y: usize, colour: Colour) {
+        let pitch = self.pitch as usize;
+        let bpp = (self.bpp / 8) as usize;
+        let pixel_offset = y * pitch + x * bpp;
+
+        // Safety: We assume the pointer to the framebuffer is valid, which it likely
+        // is because we copy it from the Limine request.
+        unsafe {
+            *(self.addr.add(pixel_offset) as *mut u32) = colour.into();
+        }
+    }
+
+    /// Writes a 2D slice `buffer` to the screen. This should be less than the
+    /// size of the screen in dimensions, but does not neccessarily fill the
+    /// whole screen.
+    pub fn render_frame(&self, buffer: &[&[Colour]]) {
+        // TODO: this should return errors.
+        for (y, &row) in buffer.iter().enumerate() {
+            if y >= self.height() as usize {
+                break;
+            }
+            for (x, pixel) in row.iter().enumerate() {
+                if x >= self.width() as usize {
+                    break;
+                }
+                self.write_pixel(x, y, *pixel);
+            }
+        }
+    }
+
+    /// Returns the width of the framebuffer in pixels.
+    pub const fn width(&self) -> u32 {
+        self.width as u32
+    }
+
+    /// Returns the height of the framebuffer in pixels.
+    pub const fn height(&self) -> u32 {
+        self.height as u32
+    }
+
+    /// Sets the new default background colour.
+    pub const fn set_default_background_colour(&mut self, bg: Colour) {
+        self.background_colour = bg;
+    }
+
+    /// Clears the screen and sets the background to the default colour.
+    pub fn clear(&self) {
+        let width = self.width as usize;
+        let height = self.height as usize;
+
+        for y in 0..height {
+            for x in 0..width {
+                // Write the background in the preferred background colour.
+                self.write_pixel(x, y, self.background_colour);
+            }
+        }
+    }
+}
+
+/// Returns the screen size in pixels or (0, 0) if something went wrong.
+pub fn screensize_px() -> (u32, u32) {
+    FRAMEBUFFER_WRITER
+        .lock()
+        .as_mut()
+        .map_or_else(|| (0, 0), |writer| (writer.width(), writer.height()))
+}

kernel/src/graphics/mod.rs

@@ -1 +1,5 @@
+pub mod ascii;
+pub mod colour;
+pub mod font;
 pub mod framebuffer;
+pub mod writer;

kernel/src/graphics/writer.rs

@@ -0,0 +1,243 @@
+#![expect(dead_code)]
+use core::fmt;
+use spin::{Lazy, Mutex};
+use x86_64::instructions::interrupts;
+
+use super::{colour::Colour, font::Font, framebuffer::FRAMEBUFFER_WRITER};
+
+static FONT_WIDTH: u32 = 8;
+static FONT_HEIGHT: u32 = 16;
+
+pub static WRITER: Lazy<Mutex<Writer>> = Lazy::new(|| Mutex::new(Writer::new()));
+
+pub fn screensize_chars() -> (u32, u32) {
+    let writer = WRITER.lock();
+    (writer.screen_width, writer.screen_height)
+}
+
+pub struct Writer {
+    font: &'static Font,
+    /// Measured in chars not pixels.
+    screen_width: u32,
+    /// Measured in chars not pixels.
+    screen_height: u32,
+    /// 16 pixels tall.
+    text_line: u32,
+    /// 8 pixels wide.
+    text_col: u32,
+
+    fg_color: Colour,
+    bg_color: Colour,
+}
+
+impl Default for Writer {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Writer {
+    pub fn new() -> Self {
+        FRAMEBUFFER_WRITER.lock().as_mut().map_or_else(
+            || {
+                panic!("Framebuffer writer not initialized.");
+            },
+            |writer| Self {
+                font: &crate::DEFAULT_FONT,
+                screen_width: writer.width() / 8,
+                screen_height: writer.height() / 16,
+                text_line: 0,
+                text_col: 0,
+                fg_color: Colour::White,
+                bg_color: Colour::Black,
+            },
+        )
+    }
+
+    pub const fn set_font(&mut self, font: &'static Font) {
+        self.font = font;
+    }
+
+    /// This is sent when the user types a backspace.
+    const BACKSPACE: u8 = 8;
+
+    pub fn write_glyph(&mut self, c: u8) {
+        if c == b'\n' {
+            self.newline();
+            return;
+        } else if c == Self::BACKSPACE {
+            self.backspace();
+            return;
+        }
+
+        // Get the character data from the font array. -- each byte is a row of
+        // pixels
+        let data: &[u8] = self.font.glyph_for(c as u16);
+
+        if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+            for (row, line) in data.iter().enumerate().take(16) {
+                for col in 0..8 {
+                    let pixel_x: u32 = self.text_col * FONT_WIDTH + col;
+                    let pixel_y: u32 = self.text_line * FONT_HEIGHT + row as u32;
+
+                    if line & (0x80 >> col) != 0 {
+                        // Write the foreground color
+                        writer.write_pixel(
+                            pixel_x as usize,
+                            pixel_y as usize,
+                            self.fg_color,
+                        );
+                    } else {
+                        // Write the background color
+                        writer.write_pixel(
+                            pixel_x as usize,
+                            pixel_y as usize,
+                            self.bg_color,
+                        );
+                    }
+                }
+            }
+        }
+
+        // Go to next position
+        if self.text_col + 1 >= self.screen_width {
+            self.newline();
+        } else {
+            self.text_col += 1;
+        }
+    }
+
+    pub const fn dimensions(&self) -> (u32, u32) {
+        (self.screen_width, self.screen_height)
+    }
+
+    pub const fn next_char(&mut self) {
+        self.text_col += 1;
+    }
+
+    pub const fn newline(&mut self) {
+        self.text_col = 0;
+
+        if self.text_line + 1 >= self.screen_height {
+            self.text_line = 0;
+        } else {
+            self.text_line += 1;
+        }
+    }
+
+    /// Handles the backspace character. TODO: Implement VT-100 style terminal
+    /// control codes alongside a shell. Not simple.
+    pub fn backspace(&mut self) {
+        if self.text_col > 0 {
+            self.text_col -= 1;
+            // Blank out the previous char.
+            self.write_glyph(b' ');
+            self.text_col -= 1;
+        }
+    }
+
+    pub fn write_string(&mut self, s: &str) {
+        for c in s.chars() {
+            self.write_glyph(c as u8);
+        }
+    }
+
+    pub const fn set_colour(&mut self, fg: Colour, bg: Colour) {
+        self.fg_color = fg;
+        self.bg_color = bg;
+    }
+
+    pub const fn reset_colour(&mut self) {
+        self.fg_color = Colour::White;
+        self.bg_color = Colour::Black;
+    }
+}
+
+impl core::fmt::Write for Writer {
+    fn write_str(&mut self, s: &str) -> core::fmt::Result {
+        self.write_string(s);
+        Ok(())
+    }
+}
+
+fn write(args: fmt::Arguments, fg: Colour, bg: Colour) {
+    use core::fmt::Write;
+
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.set_colour(fg, bg);
+        writer.write_fmt(args).unwrap();
+        writer.reset_colour();
+    });
+}
+
+pub fn _print(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::White, Colour::Black);
+    })
+}
+
+pub fn _print_err(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::Red, Colour::Black);
+    })
+}
+
+pub fn _print_log(args: fmt::Arguments) {
+    x86_64::instructions::interrupts::without_interrupts(|| {
+        write(args, Colour::Yellow, Colour::Black);
+    })
+}
+
+pub fn clear_screen() {
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.text_line = 0;
+        writer.text_col = 0;
+
+        if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+            writer.clear();
+        }
+    });
+}
+
+pub fn reset_cursor() {
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writer.text_line = 0;
+        writer.text_col = 0;
+    });
+}
+
+#[macro_export]
+macro_rules! println_log {
+    () => ($crate::print_log!("\n"));
+    ($($arg:tt)*) => ($crate::print_log!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! print_log {
+    ($($arg:tt)*) => ($crate::_print_log(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::_print(format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! printlnerr {
+    () => ($crate::printerr!("\n"));
+    ($($arg:tt)*) => ($crate::printerr!("{}\n", format_args!($($arg)*)));
+}
+
+#[macro_export]
+macro_rules! printerr {
+    ($($arg:tt)*) => ($crate::_print_err(format_args!($($arg)*)));
+}