refactor mega-commit.

- reorganised the entire project so that the entire kernel is a single codebase rather than a kernel and a libk.

kernel/src/arch/x86_64/drivers/framebuffer/colour.rs

@@ -0,0 +1,54 @@
+#[repr(u32)]
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+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,
+}
+
+#[allow(clippy::use_self)]
+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/arch/x86_64/drivers/framebuffer/display.rs

@@ -0,0 +1,104 @@
+use limine::request::FramebufferRequest;
+
+#[used]
+#[unsafe(link_section = ".requests")]
+static FRAMEBUFFER_REQUEST: FramebufferRequest = FramebufferRequest::new();
+
+use super::colour::Colour;
+use core::panic;
+
+use limine::framebuffer::Framebuffer;
+use spin::{Lazy, Mutex};
+
+pub static FRAMEBUFFER_WRITER: Lazy<Mutex<Option<FramebufferWriter>>> = Lazy::new(|| {
+    Mutex::new(FRAMEBUFFER_REQUEST.get_response().map_or_else(
+        || {
+            panic!("Framebuffer request failed");
+        },
+        |framebuffer_response| {
+            let framebuffer = framebuffer_response.framebuffers().next().unwrap();
+            Some(FramebufferWriter::new(framebuffer))
+        },
+    ))
+});
+
+/// 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,
+    bpp: u16,
+    addr: *mut u8,
+    width: u64,
+    height: u64,
+}
+
+unsafe impl Send for FramebufferWriter {}
+unsafe impl Sync for FramebufferWriter {}
+
+impl FramebufferWriter {
+    pub fn new(framebuffer: Framebuffer) -> Self {
+        Self {
+            pitch: framebuffer.pitch(),
+            bpp: framebuffer.bpp(),
+            addr: framebuffer.addr(),
+            width: framebuffer.width(),
+            height: framebuffer.height(),
+        }
+    }
+
+    pub fn write_pixel(&self, x: usize, y: usize, color: Colour) {
+        let pitch = self.pitch as usize;
+        let bpp = (self.bpp / 8) as usize;
+        let pixel_offset = y * pitch + x * bpp;
+
+        unsafe {
+            *(self.addr.add(pixel_offset) as *mut u32) = color.into();
+        }
+    }
+
+    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);
+            }
+        }
+    }
+
+    pub const fn width(&self) -> u32 {
+        self.width as u32
+    }
+
+    pub const fn height(&self) -> u32 {
+        self.height as u32
+    }
+
+    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 {
+                self.write_pixel(x, y, Colour::Black);
+            }
+        }
+    }
+}
+
+pub fn screensize_px() -> (u32, u32) {
+    FRAMEBUFFER_WRITER
+        .lock()
+        .as_mut()
+        .map_or_else(|| (0, 0), |writer| (writer.width(), writer.height()))
+}

kernel/src/arch/x86_64/drivers/framebuffer/mod.rs

@@ -0,0 +1,2 @@
+pub mod colour;
+pub mod display;