Update README to remove refs to submodules.

.cargo/config.toml

@@ -9,15 +9,16 @@ build-std-features = ["compiler-builtins-mem"]
 [env]
 RUST_TARGET_PATH = { value = "kernel", relative = true }
 
-[target.x86_64-kernel]
+# Run in debug mode.
-runner = "scripts/run.sh"
+[target.'cfg(all(target_arch = "x86_64", target_os = "none", debug_assertions))']
+runner = "scripts/run_debug.sh"
 
-[registry]
+# Otherwise we run in release mode.
-default = "gitea"
+[target.'cfg(all(target_arch = "x86_64", target_os = "none", not(debug_assertions)))']
+runner = "scripts/run_release.sh"
+
+# [registry]
+# default = "gitea"
 
 [registries.gitea]
 index = "sparse+https://git.zxq5.dev/api/packages/OsDev/cargo/" # Sparse index
-# index = "https://gitea.example.com/{owner}/_cargo-index.git" # Git
-
-# [net]
-# git-fetch-with-cli = true

.vscode/settings.json

@@ -4,6 +4,6 @@
     "[rust]": {
         "editor.defaultFormatter": "rust-lang.rust-analyzer",
         "editor.formatOnSave": true
-    }
+    },
+    "rust-analyzer.check.command": "clippy",
 }
-

Cargo.toml

@@ -4,12 +4,15 @@ resolver = "2"
 
 [workspace.package]
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
-authors = ["The Foundry OS contributors"]
+authors = ["The FoundryOS Contributors"]
 
 [profile.dev]
 opt-level = "z"
 debug = true
+# Leave this on to force Cargo to use the debug runner,
+# which adds the necessary flags for GDB debugging if you
+# set $USE_GDB (to any value) e.g. USE_GDB=1 cargo run 
 debug-assertions = true
 overflow-checks = true
 lto = false

README.md

@@ -5,18 +5,20 @@
 Here are some simple steps to get started:
 
 ```sh
-# If you have not yet cloned the repo:
+git clone https://git.zxq5.dev/OsDev/FoundryOS.git
-git clone --recurse-submodules https://git.zxq5.dev/OsDev/FoundryOS.git
-# If you already cloned the repo:
-git submodule update --init --recursive
-
-cargo build
-# This will build the binaries if required - no need to call cargo build.
 cargo run
 ```
 
+## Running in GDB:
+```sh
+USE_GDB=1 cargo run
+```
+
 ### Build dependencies
 
-* jq: checks whether the app is to be run in debugging mode.
 * libisoburn: creates ISO images to be booted from.
 * qemu: to run the kernel.
+
+Optionally,
+
+* GDB: for debugging the kernel.

kernel/Cargo.toml

@@ -1,7 +1,8 @@
 [package]
 name = "foundry_os"
-version = "0.1.0"
+edition.workspace = true
-edition = "2021"
+version.workspace = true
+authors.workspace = true
 
 [dependencies]
 limine = "0.3.1"
@@ -20,3 +21,4 @@ default = []
 [[bin]]
 name = "kernel"
 path = "src/main.rs"
+test = false

kernel/src/arch/x86_64/memmap.rs

@@ -7,11 +7,11 @@ use limine::{
 use spin::Lazy;
 
 #[used]
-#[link_section = ".requests"]
+#[unsafe(link_section = ".requests")]
 static MEMORY_MAP_REQUEST: MemoryMapRequest = MemoryMapRequest::new();
 
 #[used]
-#[link_section = ".requests"]
+#[unsafe(link_section = ".requests")]
 static HIGHER_HALF_DIRECT_MAP_REQUEST: HhdmRequest = HhdmRequest::new();
 
 /// ```rs
@@ -26,7 +26,7 @@ pub static PHYSICAL_MEMORY_OFFSET: Lazy<u64> = Lazy::new(|| {
 });
 
 #[used]
-#[link_section = ".requests"]
+#[unsafe(link_section = ".requests")]
 static KERNEL_ADDRESS_REQUEST: KernelAddressRequest = KernelAddressRequest::new();
 
 /// Converts virtual addresses in the kernel to a physical address like this:

kernel/src/arch/x86_64/memory.rs

@@ -1,6 +1,8 @@
 // use lib_alloc::allocator::FoundryAllocator;
 use limine::{memory_map::EntryType, response::MemoryMapResponse};
 use x86_64::{
+    PhysAddr,
+    VirtAddr,
     // addr,
     registers::control::Cr3,
     structures::paging::{
@@ -11,8 +13,6 @@ use x86_64::{
         PhysFrame,
         Size4KiB,
     },
-    PhysAddr,
-    VirtAddr,
 };
 
 /// Returns a mutable reference to the current level 4 page table.
@@ -27,7 +27,7 @@ unsafe fn active_l4_table(physical_memory_offset: VirtAddr) -> &'static mut Page
 
     let phys_addr = level_4_frame.start_address();
     let virt = phys_addr.as_u64() + physical_memory_offset.as_u64();
-    &mut *(virt as *mut PageTable)
+    unsafe { &mut *(virt as *mut PageTable) }
 }
 
 /// Initializes the `OffsetPageTable` for the current CPU architecture.
@@ -49,8 +49,10 @@ unsafe fn active_l4_table(physical_memory_offset: VirtAddr) -> &'static mut Page
 /// Returns an `OffsetPageTable` that allows for manipulation of the page
 /// tables for the current CPU architecture.
 pub unsafe fn init(physical_memory_offset: VirtAddr) -> OffsetPageTable<'static> {
-    let l4_table = active_l4_table(physical_memory_offset);
+    unsafe {
-    OffsetPageTable::new(l4_table, physical_memory_offset)
+        let l4_table = active_l4_table(physical_memory_offset);
+        OffsetPageTable::new(l4_table, physical_memory_offset)
+    }
 }
 
 pub(crate) struct FoundryOSFrameAllocator {
@@ -76,7 +78,7 @@ impl FoundryOSFrameAllocator {
     /// Yields one `PhysFrame` for each available 4KiB frame in the memory map.
     ///
     /// This function is used to allocate frames for the pagemap.
-    fn usable_frames(&self) -> impl Iterator<Item = PhysFrame> {
+    fn usable_frames(&self) -> impl Iterator<Item = PhysFrame> + use<> {
         let regions = self.memory_map.entries().iter();
         let usable_regions = regions.filter(|region| region.entry_type == EntryType::USABLE);
 

kernel/src/lib.rs

@@ -18,7 +18,7 @@ mod arch;
 /// Be sure to mark all limine requests with #[used], otherwise they may be removed by the compiler.
 #[used]
 // The .requests section allows limine to find the requests faster and more safely.
-#[link_section = ".requests"]
+#[unsafe(link_section = ".requests")]
 static BASE_REVISION: BaseRevision = BaseRevision::new();
 
 #[panic_handler]

kernel/src/main.rs

@@ -9,7 +9,7 @@ use libk::{
     scheduling::task::{Executor, Task},
 };
 
-#[no_mangle]
+#[unsafe(no_mangle)]
 extern "C" fn kmain() -> ! {
     println_log!(" [ Initialising Kernel Systems ] ");
     if let Err(err) = foundry_os::boot() {

libk/src/io/ascii.rs

@@ -3,7 +3,7 @@ use spin::{Lazy, Mutex};
 use x86_64::instructions::interrupts;
 
 pub use super::framebuffer::screensize_px;
-use super::framebuffer::{Color, FRAMEBUFFER_WRITER};
+use super::framebuffer::{Colour, FRAMEBUFFER_WRITER};
 
 mod font;
 use font::FONT;
@@ -28,32 +28,39 @@ pub struct Writer {
     /// 8 pixels wide.
     text_col: u32,
 
-    fg_color: Color,
+    fg_color: Colour,
-    bg_color: Color,
+    bg_color: Colour,
 
     offset1: usize,
     offset2: usize,
 }
 
+impl Default for Writer {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Writer {
     pub fn new() -> Self {
-        if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+        FRAMEBUFFER_WRITER.lock().as_mut().map_or_else(
-            Self {
+            || {
-                screen_width: writer.width() as u32 / 8,
+                panic!("Framebuffer writer not initialized.");
-                screen_height: writer.height() as u32 / 16,
+            },
+            |writer| Self {
+                screen_width: writer.width() / 8,
+                screen_height: writer.height() / 16,
                 text_line: 0,
                 text_col: 0,
-                fg_color: Color::White,
+                fg_color: Colour::White,
-                bg_color: Color::Black,
+                bg_color: Colour::Black,
                 offset1: 16,
                 offset2: 0,
-            }
+            },
-        } else {
+        )
-            panic!("Framebuffer writer not initialized");
-        }
     }
 
-    pub fn write_char(&mut self, c: u16) {
+    pub fn write_glyph(&mut self, c: u16) {
         if c as u8 == b'\n' {
             self.newline();
             return;
@@ -63,8 +70,7 @@ impl Writer {
         let data: &[u8] = &FONT[c as usize * 16..(c as usize + 1) * 16];
 
         if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
-            for row in 0..16 {
+            for (row, line) in data.iter().enumerate().take(16) {
-                let line: u8 = data[row];
                 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;
@@ -88,20 +94,20 @@ impl Writer {
         }
     }
 
-    pub fn set_offset(&mut self, offset1: usize, offset2: usize) {
+    pub const fn set_offset(&mut self, offset1: usize, offset2: usize) {
         self.offset1 = offset1;
         self.offset2 = offset2;
     }
 
-    pub fn dimensions(&self) -> (u32, u32) {
+    pub const fn dimensions(&self) -> (u32, u32) {
         (self.screen_width, self.screen_height)
     }
 
-    pub fn next_char(&mut self) {
+    pub const fn next_char(&mut self) {
         self.text_col += 1;
     }
 
-    pub fn newline(&mut self) {
+    pub const fn newline(&mut self) {
         self.text_col = 0;
 
         if self.text_line + 1 >= self.screen_height {
@@ -113,18 +119,18 @@ impl Writer {
 
     pub fn write_string(&mut self, s: &str) {
         for c in s.chars() {
-            self.write_char(c as u16);
+            self.write_glyph(c as u16);
         }
     }
 
-    pub fn set_colour(&mut self, fg: Color, bg: Color) {
+    pub const fn set_colour(&mut self, fg: Colour, bg: Colour) {
         self.fg_color = fg;
         self.bg_color = bg;
     }
 
-    pub fn reset_colour(&mut self) {
+    pub const fn reset_colour(&mut self) {
-        self.fg_color = Color::White;
+        self.fg_color = Colour::White;
-        self.bg_color = Color::Black;
+        self.bg_color = Colour::Black;
     }
 }
 
@@ -135,7 +141,7 @@ impl core::fmt::Write for Writer {
     }
 }
 
-fn write(args: fmt::Arguments, fg: Color, bg: Color) {
+fn write(args: fmt::Arguments, fg: Colour, bg: Colour) {
     use core::fmt::Write;
 
     interrupts::without_interrupts(|| {
@@ -148,19 +154,19 @@ fn write(args: fmt::Arguments, fg: Color, bg: Color) {
 
 pub fn _print(args: fmt::Arguments) {
     x86_64::instructions::interrupts::without_interrupts(|| {
-        write(args, Color::White, Color::Black);
+        write(args, Colour::White, Colour::Black);
     })
 }
 
 pub fn _print_err(args: fmt::Arguments) {
     x86_64::instructions::interrupts::without_interrupts(|| {
-        write(args, Color::Red, Color::Black);
+        write(args, Colour::Red, Colour::Black);
     })
 }
 
 pub fn _print_log(args: fmt::Arguments) {
     x86_64::instructions::interrupts::without_interrupts(|| {
-        write(args, Color::Yellow, Color::Black);
+        write(args, Colour::Yellow, Colour::Black);
     })
 }
 

libk/src/io/framebuffer.rs

@@ -1,52 +1,69 @@
 use limine::request::FramebufferRequest;
 
 #[used]
-#[link_section = ".requests"]
+#[unsafe(link_section = ".requests")]
 static FRAMEBUFFER_REQUEST: FramebufferRequest = FramebufferRequest::new();
 
 mod colour;
 
-pub use colour::Color;
+pub use colour::Colour;
 use core::panic;
 
 use limine::framebuffer::Framebuffer;
 use spin::{Lazy, Mutex};
 
-// use crate::{colour::Color, FRAMEBUFFER_REQUEST};
-
 pub static FRAMEBUFFER_WRITER: Lazy<Mutex<Option<FramebufferWriter>>> = Lazy::new(|| {
-    Mutex::new(
+    Mutex::new(FRAMEBUFFER_REQUEST.get_response().map_or_else(
-        if let Some(framebuffer_response) = FRAMEBUFFER_REQUEST.get_response() {
+        || {
-            let framebuffer = framebuffer_response.framebuffers().next().unwrap();
-            Some(FramebufferWriter::new(framebuffer))
-        } else {
             panic!("Framebuffer request failed");
         },
-    )
+        |framebuffer_response| {
+            let framebuffer = framebuffer_response.framebuffers().next().unwrap();
+            Some(FramebufferWriter::new(framebuffer))
+        },
+    ))
 });
 
-pub struct FramebufferWriter<'a> {
+/// The updated writer stores necessary fields from the [Framebuffer].
-    framebuffer: Framebuffer<'a>,
+/// 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<'a> Send for FramebufferWriter<'a> {}
+unsafe impl Send for FramebufferWriter {}
-unsafe impl<'a> Sync for FramebufferWriter<'a> {}
+unsafe impl Sync for FramebufferWriter {}
-impl<'a> FramebufferWriter<'a> {
-    pub fn new(framebuffer: Framebuffer<'a>) -> Self {
-        Self { framebuffer }
-    }
 
-    pub fn write_pixel(&self, x: usize, y: usize, color: Color) {
+impl FramebufferWriter {
-        let pitch = self.framebuffer.pitch() as usize;
+    pub fn new(framebuffer: Framebuffer) -> Self {
-        let bpp = (self.framebuffer.bpp() / 8) as usize;
+        Self {
-        let pixel_offset = y * pitch + x * bpp;
+            pitch: framebuffer.pitch(),
-
+            bpp: framebuffer.bpp(),
-        unsafe {
+            addr: framebuffer.addr(),
-            *(self.framebuffer.addr().add(pixel_offset) as *mut u32) = color.into();
+            width: framebuffer.width(),
+            height: framebuffer.height(),
         }
     }
 
-    pub fn render_frame(&self, buffer: &[Color; 1280 * 800]) {
+    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; 1280 * 800]) {
         for (y, row) in buffer.chunks(1280).enumerate() {
             for (x, pixel) in row.iter().enumerate() {
                 self.write_pixel(x, y, *pixel);
@@ -54,30 +71,29 @@ impl<'a> FramebufferWriter<'a> {
         }
     }
 
-    pub fn width(&self) -> u32 {
+    pub const fn width(&self) -> u32 {
-        self.framebuffer.width() as u32
+        self.width as u32
     }
 
-    pub fn height(&self) -> u32 {
+    pub const fn height(&self) -> u32 {
-        self.framebuffer.height() as u32
+        self.height as u32
     }
 
     pub fn clear(&self) {
-        let width = self.framebuffer.width() as usize;
+        let width = self.width as usize;
-        let height = self.framebuffer.height() as usize;
+        let height = self.height as usize;
 
         for y in 0..height {
             for x in 0..width {
-                self.write_pixel(x, y, Color::Black);
+                self.write_pixel(x, y, Colour::Black);
             }
         }
     }
 }
 
 pub fn screensize_px() -> (u32, u32) {
-    if let Some(writer) = FRAMEBUFFER_WRITER.lock().as_mut() {
+    FRAMEBUFFER_WRITER
-        (writer.width(), writer.height())
+        .lock()
-    } else {
+        .as_mut()
-        (0, 0)
+        .map_or_else(|| (0, 0), |writer| (writer.width(), writer.height()))
-    }
 }

libk/src/io/framebuffer/colour.rs

@@ -1,6 +1,6 @@
 #[repr(u32)]
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
-pub enum Color {
+pub enum Colour {
     ARGB(u8, u8, u8, u8),
     RGB(u8, u8, u8),
     HexARGB(u32),
@@ -14,40 +14,41 @@ pub enum Color {
     White = 0xFFFFFFFF,
 }
 
-impl Into<u32> for Color {
+#[allow(clippy::use_self)]
-    fn into(self) -> u32 {
+impl From<Colour> for u32 {
-        match self {
+    fn from(val: Colour) -> Self {
-            Color::ARGB(a, r, g, b) => {
+        match val {
+            Colour::ARGB(a, r, g, b) => {
                 (a as u32) << 24 | (r as u32) << 16 | (g as u32) << 8 | (b as u32)
             }
-            Color::RGB(r, g, b) => (0u32) << 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),
-            Color::HexARGB(hex) => hex,
+            Colour::HexARGB(hex) => hex,
-            Color::Black => 0xFF000000,
+            Colour::Black => 0xFF000000,
-            Color::Blue => 0xFF0000FF,
+            Colour::Blue => 0xFF0000FF,
-            Color::Green => 0xFF00FF00,
+            Colour::Green => 0xFF00FF00,
-            Color::Cyan => 0xFF00FFFF,
+            Colour::Cyan => 0xFF00FFFF,
-            Color::Red => 0xFFFF0000,
+            Colour::Red => 0xFFFF0000,
-            Color::Magenta => 0xFFFF00FF,
+            Colour::Magenta => 0xFFFF00FF,
-            Color::Yellow => 0xFFFFFF00,
+            Colour::Yellow => 0xFFFFFF00,
-            Color::White => 0xFFFFFFFF,
+            Colour::White => 0xFFFFFFFF,
         }
     }
 }
 
-impl core::fmt::Display for Color {
+impl core::fmt::Display for Colour {
     fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         match self {
-            Color::ARGB(r, g, b, a) => write!(f, "RGBA(#{:x}{:x}{:x}{:x})", r, g, b, a),
+            Self::ARGB(r, g, b, a) => write!(f, "RGBA(#{:x}{:x}{:x}{:x})", r, g, b, a),
-            Color::RGB(r, g, b) => write!(f, "RGB(#{:x}{:x}{:x})", r, g, b),
+            Self::RGB(r, g, b) => write!(f, "RGB(#{:x}{:x}{:x})", r, g, b),
-            Color::HexARGB(hex) => write!(f, "Hex(#{:x})", hex),
+            Self::HexARGB(hex) => write!(f, "Hex(#{:x})", hex),
-            Color::Black => write!(f, "Black"),
+            Self::Black => write!(f, "Black"),
-            Color::Blue => write!(f, "Blue"),
+            Self::Blue => write!(f, "Blue"),
-            Color::Green => write!(f, "Green"),
+            Self::Green => write!(f, "Green"),
-            Color::Cyan => write!(f, "Cyan"),
+            Self::Cyan => write!(f, "Cyan"),
-            Color::Red => write!(f, "Red"),
+            Self::Red => write!(f, "Red"),
-            Color::Magenta => write!(f, "Magenta"),
+            Self::Magenta => write!(f, "Magenta"),
-            Color::Yellow => write!(f, "Yellow"),
+            Self::Yellow => write!(f, "Yellow"),
-            Color::White => write!(f, "White"),
+            Self::White => write!(f, "White"),
         }
     }
 }

libk/src/io/keyboard.rs

@@ -5,9 +5,9 @@ use core::{
     task::{Context, Poll},
 };
 
-use super::{print, println};
+use crate::prelude::*;
 use crossbeam::queue::ArrayQueue;
-use futures_util::{task::AtomicWaker, Stream};
+use futures_util::{Stream, task::AtomicWaker};
 use spin::Once;
 
 static KBD_QUEUE: Once<ArrayQueue<u8>> = Once::new();
@@ -15,7 +15,7 @@ static WAKER: AtomicWaker = AtomicWaker::new();
 
 pub fn add_scancode(scancode: u8) {
     if let Some(queue) = KBD_QUEUE.get() {
-        if let Err(_) = queue.push(scancode) {
+        if queue.push(scancode).is_err() {
             println!("WARNING: scancode queue full; dropping keyboard input");
         } else {
             println!("waking waker");
@@ -33,7 +33,14 @@ pub struct ScanCodeStream {
 impl ScanCodeStream {
     pub fn new() -> Self {
         KBD_QUEUE.call_once(|| ArrayQueue::new(5));
-        ScanCodeStream { _private: () }
+
+        Self { _private: () }
+    }
+}
+
+impl Default for ScanCodeStream {
+    fn default() -> Self {
+        Self::new()
     }
 }
 
@@ -42,30 +49,30 @@ impl Stream for ScanCodeStream {
 
     fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         let queue = KBD_QUEUE.get().expect("scancode queue not initialized");
-        print!("polling or smth");
+        serial_println!("This is called once.");
+        WAKER.register(cx.waker());
 
         // fast path
         if let Some(scancode) = queue.pop() {
             return Poll::Ready(Some(scancode));
         }
 
-        WAKER.register(&cx.waker());
+        queue.pop().map_or_else(
-        match queue.pop() {
+            || {
-            Some(scancode) => {
+                print!("Returning");
-                print!("scancode found");
+                Poll::Pending
+            },
+            |scancode| {
+                print!("Scancode found");
                 WAKER.take();
                 Poll::Ready(Some(scancode))
-            }
+            },
-            None => {
+        )
-                print!("returning");
-                Poll::Pending
-            }
-        }
     }
 }
 
 use futures_util::stream::StreamExt;
-use pc_keyboard::{layouts, DecodedKey, HandleControl, Keyboard, ScancodeSet1};
+use pc_keyboard::{DecodedKey, HandleControl, Keyboard, ScancodeSet1, layouts};
 
 pub async fn print_keypresses() {
     let mut scancodes = ScanCodeStream::new();
@@ -75,7 +82,7 @@ pub async fn print_keypresses() {
         HandleControl::Ignore,
     );
 
-    println!("OK!!!");
+    serial_println!("Printing keypresses.");
 
     while let Some(scancode) = scancodes.next().await {
         if let Ok(Some(key_event)) = keyboard.add_byte(scancode) {

libk/src/io/port.rs

@@ -3,23 +3,27 @@
 use core::arch::asm;
 
 #[inline]
-pub unsafe fn inb(port: u16) -> u8 {
+pub fn inb(port: u16) -> u8 {
     let value: u8;
-    asm!(
+    unsafe {
-        "in al, dx",
+        asm!(
-        out("al") value,
+            "in al, dx",
-        in("dx") port,
+            out("al") value,
-        options(nomem, nostack, preserves_flags)
+            in("dx") port,
-    );
+            options(nomem, nostack, preserves_flags)
+        );
+    }
     value
 }
 
 #[inline]
-pub unsafe fn outb(port: u16, value: u8) {
+pub fn outb(port: u16, value: u8) {
-    asm!(
+    unsafe {
-        "out dx, al",
+        asm!(
-        in("dx") port,
+            "out dx, al",
-        in("al") value,
+            in("dx") port,
-        options(nomem, nostack, preserves_flags)
+            in("al") value,
-    );
+            options(nomem, nostack, preserves_flags)
+        );
+    }
 }

libk/src/io/serial.rs

@@ -45,14 +45,14 @@ pub fn serial_read() -> &'static str {
 
     let i = BUFFER_LEN.load(Ordering::SeqCst);
 
-    return unsafe {
+    unsafe {
         if i != 0 {
             core::str::from_utf8(&BUFFER[..i - 1]).unwrap()
         } else {
             serial_println!("empty string");
             ""
         }
-    };
+    }
 }
 
 static PORT: u16 = 0x3f8;
@@ -83,15 +83,13 @@ impl Writer {
     pub fn write_byte(&self, data: u8) {
         unsafe {
             while !self.write_success() {}
-            outb(PORT + 0, data);
+            outb(PORT, data);
         }
     }
 }
 
 pub fn init() -> Result<(), &'static str> {
-    if let Err(e) = test() {
+    test()?;
-        return Err(e);
-    }
 
     if READER.lock().is_none() {
         *READER.lock() = Some(Reader);
@@ -105,24 +103,22 @@ pub fn init() -> Result<(), &'static str> {
 }
 
 pub fn test() -> Result<(), &'static str> {
-    unsafe {
+    outb(PORT + 1, 0x00); // Disable all interrupts
-        outb(PORT + 1, 0x00); // Disable all interrupts
+    outb(PORT + 3, 0x80); // Enable DLAB (set baud rate divisor)
-        outb(PORT + 3, 0x80); // Enable DLAB (set baud rate divisor)
+    outb(PORT, 0x03); // Set divisor to 3 (lo byte) 38400 baud
-        outb(PORT + 0, 0x03); // Set divisor to 3 (lo byte) 38400 baud
+    outb(PORT + 1, 0x00); //                  (hi byte)
-        outb(PORT + 1, 0x00); //                  (hi byte)
+    outb(PORT + 3, 0x03); // 8 bits, no parity, one stop bit
-        outb(PORT + 3, 0x03); // 8 bits, no parity, one stop bit
+    outb(PORT + 2, 0xC7); // Enable FIFO, clear them, with 14-bytethreshold
-        outb(PORT + 2, 0xC7); // Enable FIFO, clear them, with 14-bytethreshold
+    outb(PORT + 4, 0x0B); // IRQs enabled, RTS/DSR set
-        outb(PORT + 4, 0x0B); // IRQs enabled, RTS/DSR set
+    outb(PORT + 4, 0x1E); // Set in loopback mode, test the serial chip
-        outb(PORT + 4, 0x1E); // Set in loopback mode, test the serial chip
+    outb(PORT, 0xAE); // Test serial chip (send byte 0xAE and check if serial returns same byte)
-        outb(PORT + 0, 0xAE); // Test serial chip (send byte 0xAE and check if serial returns same byte)
 
-        if inb(PORT + 0) != 0xAE {
+    if inb(PORT) != 0xAE {
-            return Err("serial test failed");
+        return Err("serial test failed");
-        }
-
-        outb(PORT + 4, 0x0F);
     }
 
+    outb(PORT + 4, 0x0F);
+
     Ok(())
 }
 
@@ -153,7 +149,7 @@ impl Reader {
     pub fn read(&self) -> u8 {
         unsafe {
             while !self.read_ready() {}
-            return inb(PORT + 0);
+            inb(PORT)
         }
     }
 }

libk/src/lib.rs

@@ -1,5 +1,6 @@
 #![no_std]
-
+#![warn(tail_expr_drop_order)]
+#![warn(clippy::correctness, clippy::perf, clippy::nursery)]
 // alloc
 // io : serial, framebuffer, ascii(?), keyboard
 // ?????
@@ -11,5 +12,5 @@ pub mod scheduling;
 
 /// Re-exports most of the IO macros.
 pub mod prelude {
-    pub use crate::{print_log, println, println_log, serial_print, serial_println};
+    pub use crate::{print, print_log, println, println_log, serial_print, serial_println};
 }

libk/src/scheduling/task.rs

@@ -14,8 +14,8 @@ pub struct Task {
 }
 
 impl Task {
-    pub fn new(future: impl Future<Output = ()> + 'static) -> Task {
+    pub fn new(future: impl Future<Output = ()> + 'static) -> Self {
-        Task {
+        Self {
             id: TaskId::new(),
             future: Box::pin(future),
         }
@@ -32,9 +32,15 @@ pub struct Executor {
     waker_cache: BTreeMap<TaskId, Waker>,
 }
 
+impl Default for Executor {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl Executor {
     pub fn new() -> Self {
-        Executor {
+        Self {
             tasks: BTreeMap::new(),
             task_queue: Arc::new(ArrayQueue::new(100)),
             waker_cache: BTreeMap::new(),
@@ -63,7 +69,7 @@ impl Executor {
             };
             let waker = waker_cache
                 .entry(task_id)
-                .or_insert_with(|| TaskWaker::new(task_id, task_queue.clone()));
+                .or_insert_with(|| TaskWaker::waker(task_id, task_queue.clone()));
             let mut context = Context::from_waker(waker);
             match task.poll(&mut context) {
                 Poll::Ready(()) => {
@@ -98,8 +104,8 @@ struct TaskWaker {
 }
 
 impl TaskWaker {
-    fn new(task_id: TaskId, task_queue: Arc<ArrayQueue<TaskId>>) -> Waker {
+    fn waker(task_id: TaskId, task_queue: Arc<ArrayQueue<TaskId>>) -> Waker {
-        Waker::from(Arc::new(TaskWaker {
+        Waker::from(Arc::new(Self {
             task_id,
             task_queue,
         }))
@@ -128,6 +134,6 @@ struct TaskId(u64);
 impl TaskId {
     fn new() -> Self {
         static NEXT: AtomicU64 = AtomicU64::new(0);
-        TaskId(NEXT.fetch_add(1, Ordering::Relaxed))
+        Self(NEXT.fetch_add(1, Ordering::Relaxed))
     }
 }

scripts/run_debug.sh

@@ -1,5 +1,7 @@
 #!/bin/bash
 
+# Script originally written by zxq5, I added separate scripts to remove `jq` dependency.
+
 # Colors
 GREEN='\033[0;32m'
 BLUE='\033[0;34m'
@@ -16,6 +18,8 @@ trap 'echo -e "${RED}${BOLD}error${NC}: build failed" >&2' ERR
 script_dir=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
 project_root=$(cd "$script_dir/.." &>/dev/null && pwd)
 
+echo -e "${GREEN}${BOLD} Running kernel in debug mode."
+
 # Logging functions
 info() {
     echo -e "${BLUE}${BOLD}info${NC}: $1"
@@ -124,8 +128,8 @@ else
     kvm_flag=""
 fi
 
-# Check if we're running in debug mode
+# Enable using GDB with $USE_GDB.
-if [[ "$(cargo metadata --format-version=1 | jq -r '.workspace_members[0]' | cut -d' ' -f2)" == "(debug)" ]]; then
+if [ $USE_GDB ]; then
     debug_flags="-s -S"
 else
     debug_flags=""

scripts/run_release.sh

@@ -0,0 +1,186 @@
+#!/bin/bash
+
+# Script originally written by zxq5, I added separate scripts to remove `jq` dependency.
+
+# Colors
+GREEN='\033[0;32m'
+BLUE='\033[0;34m'
+YELLOW='\033[0;33m'
+RED='\033[0;31m'
+BOLD='\033[1m'
+NC='\033[0m' # No Color
+
+# Error handling
+set -e
+trap 'echo -e "${RED}${BOLD}error${NC}: build failed" >&2' ERR
+
+# Get absolute path to project root
+script_dir=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" &>/dev/null && pwd)
+project_root=$(cd "$script_dir/.." &>/dev/null && pwd)
+
+echo -e "${GREEN}${BOLD} Running kernel in release mode."
+
+# Logging functions
+info() {
+    echo -e "${BLUE}${BOLD}info${NC}: $1"
+}
+
+compiling() {
+    echo -e "${GREEN}${BOLD}Compiling${NC}: $1"
+}
+
+warning() {
+    echo -e "${YELLOW}${BOLD}warning${NC}: $1" >&2
+}
+
+building() {
+    echo -e "${GREEN}${BOLD}Building${NC}: $1"
+}
+
+copying() {
+    echo -e "${GREEN}${BOLD}  Copying${NC}: $1 to $2"
+}
+
+error() {
+    echo -e "${RED}${BOLD}error${NC}: $1" >&2
+    exit 1
+}
+
+copy_file() {
+    copying $1 $2
+    cp "$1" "$2" || error $3
+}
+
+build_dir="$project_root/build"
+iso_root="$build_dir/iso_root"
+
+# Check if we're running tests
+is_test=0
+if [[ $1 == *"deps"* ]]; then
+    is_test=1
+    kernel_path="$1"
+else
+    # Build the kernel normally
+    cd "$project_root"
+    # cargo build
+    kernel_path="$build_dir/target/x86_64-kernel/release/kernel"
+fi
+
+# Check for required tools
+check_tools() {
+    local missing=0
+    for tool in xorriso git qemu-system-x86_64; do
+        if ! command -v $tool >/dev/null 2>&1; then
+            error "required tool '$tool' is not installed"
+            missing=1
+        fi
+    done
+    if [ $missing -eq 1 ]; then
+        error "missing required tools"
+    fi
+}
+
+# Create build directory structure
+info "Creating build directory structure"
+mkdir -p "$iso_root/boot/limine"
+mkdir -p "$iso_root/EFI/BOOT"
+
+# Clone Limine if needed
+if [ ! -d "$build_dir/limine" ]; then
+    compiling "limine bootloader"
+    cd "$build_dir"
+    git clone https://github.com/limine-bootloader/limine.git --branch=v9.x-binary --depth=1 "$build_dir/limine" || error "failed to clone limine"
+    make -C "$build_dir/limine" || error "failed to build limine"
+    cd "$project_root"
+fi
+
+# Copy files
+info "Copying files to ISO root"
+copy_file "$kernel_path" "$iso_root/boot/kernel" "failed to copy kernel"
+copy_file "$project_root/config/limine.conf" "$iso_root/boot/limine/limine.conf" "failed to copy limine config"
+copy_file "$build_dir/limine/limine-bios-cd.bin" "$iso_root/boot/limine/" "failed to copy limine-bios-cd.bin"
+copy_file "$build_dir/limine/limine-uefi-cd.bin" "$iso_root/boot/limine/" "failed to copy limine-uefi-cd.bin"
+copy_file "$build_dir/limine/limine-bios.sys" "$iso_root/boot/limine/" "failed to copy limine-bios.sys"
+copy_file "$build_dir/limine/BOOTX64.EFI" "$iso_root/EFI/BOOT/" "failed to copy BOOTX64.EFI"
+copy_file "$build_dir/limine/BOOTIA32.EFI" "$iso_root/EFI/BOOT/" "failed to copy BOOTIA32.EFI"
+
+# Create ISO
+building "bootable ISO image"
+xorriso -as mkisofs -R -r -J -b boot/limine/limine-bios-cd.bin \
+        -no-emul-boot -boot-load-size 4 -boot-info-table -hfsplus \
+        -apm-block-size 2048 --efi-boot boot/limine/limine-uefi-cd.bin \
+        -efi-boot-part --efi-boot-image --protective-msdos-label \
+        "$iso_root" -o "$build_dir/image.iso" || error "failed to create ISO"
+
+# Install Limine
+info "Installing Limine bootloader"
+"$build_dir/limine/limine" bios-install "$build_dir/image.iso" || error "failed to install limine"
+
+# Check if KVM is available
+if [ "${KVM_FLAG:-enable}" = "disable" ]; then
+    warning "KVM acceleration disabled by user"
+    kvm_flag=""
+elif [ -c "/dev/kvm" ] && [ -w "/dev/kvm" ]; then
+    info "KVM acceleration enabled"
+    kvm_flag="-enable-kvm"
+else
+    warning "KVM acceleration not available (is kvm module loaded?)"
+    kvm_flag=""
+fi
+
+# I'm lazy but I just remove GDB flags when running this script.
+debug_flags=""
+
+# Set up test-specific flags
+if [ $is_test -eq 1 ]; then
+    test_flags="-device isa-debug-exit,iobase=0xf4,iosize=0x04 -display none"
+    serial_flags="-serial stdio"
+else
+    test_flags=""
+    # serial_flags="-serial tcp:127.0.0.1:1234,server -monitor telnet:127.0.0.1:1235,server"
+    serial_flags="-serial stdio"
+fi
+
+# Run in QEMU
+if [[ ${QEMU_FLAGS} == *-S* ]]; then
+    info "Running OS in QEMU with GDB debugging enabled"
+    info "To connect GDB, run: gdb"
+    info "At the GDB prompt, type: target remote localhost:1234"
+else
+    info "Running OS in QEMU..."
+fi
+
+check_test_res() {
+    qemu_exit_code=$?
+    if [ $qemu_exit_code -eq 33 ]; then
+        # Success case (0x10 << 1) | 1 = 33
+        info "All tests passed"
+        exit 0
+    elif [ $qemu_exit_code -eq 35 ]; then
+        # Failure case (0x11 << 1) | 1 = 35
+        warning "Some tests failed"
+        exit 1
+    else
+        # Any other exit code is treated as a failure
+        warning "Some tests failed"
+        exit 1
+    fi
+}
+
+
+kvm_flag=""
+
+trap 'check_test_res "tests completed"' ERR
+ 
+cd "$project_root"
+qemu-system-x86_64 -M q35 \
+    ${kvm_flag} \
+    -cdrom "$build_dir/image.iso" \
+    -boot d \
+    -m 2G \
+    ${serial_flags} \
+    -no-reboot \
+    ${test_flags} \
+    ${debug_flags} \
+    ${QEMU_FLAGS:-}
+