Merge branch 'post-02' into post-03

Merge pull request #1436 from phil-opp/post-02-fix-target
Fix: `target-pointer-width` field now expects an integer
2025-12-16 14:27:49 +00:00 · 2025-09-03 17:58:28 +02:00 · 2025-09-03 17:56:38 +02:00 · 2025-09-03 17:53:14 +02:00 · 2025-09-03 17:52:56 +02:00
18 changed files with 18 additions and 890 deletions
--- a/.cargo/config.toml
+++ b/.cargo/config.toml
@@ -1,5 +1,5 @@
 [unstable]
-build-std = ["core", "compiler_builtins", "alloc"]
+build-std = ["core", "compiler_builtins"]
 build-std-features = ["compiler-builtins-mem"]

 [build]
--- a/.github/workflows/code.yml
+++ b/.github/workflows/code.yml
@@ -67,31 +67,6 @@ jobs:
        with:
          command: bootimage

-      # install QEMU
-      - name: Install QEMU (Linux)
-        run: sudo apt update && sudo apt install qemu-system-x86
-        if: runner.os == 'Linux'
-      - name: Install QEMU (macOS)
-        run: brew install qemu
-        if: runner.os == 'macOS'
-        env:
-          HOMEBREW_NO_AUTO_UPDATE: 1
-          HOMEBREW_NO_BOTTLE_SOURCE_FALLBACK: 1
-          HOMEBREW_NO_INSTALL_CLEANUP: 1
-      - name: Install QEMU (Windows)
-        run: |
-          choco install qemu --version 2021.5.5
-          echo "$Env:Programfiles\qemu" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
-        if: runner.os == 'Windows'
-        shell: pwsh
-      - name: "Print QEMU Version"
-        run: qemu-system-x86_64 --version
-
-      - name: Run `cargo test`
-        uses: actions-rs/cargo@v1
-        with:
-          command: test
-
  check_formatting:
    name: Check Formatting
    runs-on: ubuntu-latest
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,50 +2,21 @@
 # It is not intended for manual editing.
 version = 4

-[[package]]
-name = "autocfg"
-version = "1.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
-
-[[package]]
-name = "bit_field"
-version = "0.10.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc827186963e592360843fb5ba4b973e145841266c1357f7180c43526f2e5b61"
-
-[[package]]
-name = "bitflags"
-version = "1.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
-
-[[package]]
-name = "bitflags"
-version = "2.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a65b545ab31d687cff52899d4890855fec459eb6afe0da6417b8a18da87aa29"
-
 [[package]]
 name = "blog_os"
 version = "0.1.0"
 dependencies = [
 "bootloader",
 "lazy_static",
- "linked_list_allocator",
- "pc-keyboard",
- "pic8259",
 "spin 0.5.2",
- "uart_16550",
- "volatile 0.2.7",
- "x86_64",
+ "volatile",
 ]

 [[package]]
 name = "bootloader"
-version = "0.9.32"
+version = "0.9.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1ea119c3ed05625c179e09d17d0914570a3753ca09c890a73d98f6b72aea00d2"
+checksum = "7bdfddac270bbdd45903296bc1caf29a7fdce6b326aaf0bbab7f04c5f98b7447"

 [[package]]
 name = "lazy_static"
@@ -56,52 +27,6 @@ dependencies = [
 "spin 0.9.8",
 ]

-[[package]]
-name = "linked_list_allocator"
-version = "0.9.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "549ce1740e46b291953c4340adcd74c59bcf4308f4cac050fd33ba91b7168f4a"
-dependencies = [
- "spinning_top",
-]
-
-[[package]]
-name = "lock_api"
-version = "0.4.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96936507f153605bddfcda068dd804796c84324ed2510809e5b2a624c81da765"
-dependencies = [
- "autocfg",
- "scopeguard",
-]
-
-[[package]]
-name = "pc-keyboard"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed089a1fbffe3337a1a345501c981f1eb1e47e69de5a40e852433e12953c3174"
-
-[[package]]
-name = "pic8259"
-version = "0.10.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb844b5b01db1e0b17938685738f113bfc903846f18932b378bc0eabfa40e194"
-dependencies = [
- "x86_64",
-]
-
-[[package]]
-name = "rustversion"
-version = "1.0.22"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d"
-
-[[package]]
-name = "scopeguard"
-version = "1.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
-
 [[package]]
 name = "spin"
 version = "0.5.2"
@@ -114,46 +39,8 @@ version = "0.9.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"

-[[package]]
-name = "spinning_top"
-version = "0.2.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b9eb1a2f4c41445a3a0ff9abc5221c5fcd28e1f13cd7c0397706f9ac938ddb0"
-dependencies = [
- "lock_api",
-]
-
-[[package]]
-name = "uart_16550"
-version = "0.2.19"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "614ff2a87880d4bd4374722268598a970bbad05ced8bf630439417347254ab2e"
-dependencies = [
- "bitflags 1.3.2",
- "rustversion",
- "x86_64",
-]
-
 [[package]]
 name = "volatile"
 version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f6b06ad3ed06fef1713569d547cdbdb439eafed76341820fb0e0344f29a41945"
-
-[[package]]
-name = "volatile"
-version = "0.4.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "442887c63f2c839b346c192d047a7c87e73d0689c9157b00b53dcc27dd5ea793"
-
-[[package]]
-name = "x86_64"
-version = "0.14.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c101112411baafbb4bf8d33e4c4a80ab5b02d74d2612331c61e8192fc9710491"
-dependencies = [
- "bit_field",
- "bitflags 2.9.2",
- "rustversion",
- "volatile 0.4.6",
-]
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,23 +4,10 @@ version = "0.1.0"
 authors = ["Philipp Oppermann <dev@phil-opp.com>"]
 edition = "2024"

-[[test]]
-name = "should_panic"
-harness = false
-
-[[test]]
-name = "stack_overflow"
-harness = false
-
 [dependencies]
-bootloader = { version = "0.9", features = ["map_physical_memory"] }
+bootloader = "0.9"
 volatile = "0.2.6"
 spin = "0.5.2"
-x86_64 = "0.14.2"
-uart_16550 = "0.2.0"
-pic8259 = "0.10.1"
-pc-keyboard = "0.7.0"
-linked_list_allocator = "0.9.0"

 [dependencies.lazy_static]
 version = "1.0"
@@ -28,17 +15,5 @@ features = ["spin_no_std"]

 [[bin]]
 name = "blog_os"
-test = true
+test = false
 bench = false
-
-
-[package.metadata.bootimage]
-test-args = [
-    "-device",
-    "isa-debug-exit,iobase=0xf4,iosize=0x04",
-    "-serial",
-    "stdio",
-    "-display",
-    "none",
-]
-test-success-exit-code = 33 # (0x10 << 1) | 1
--- a/README.md
+++ b/README.md
@@ -1,10 +1,10 @@
-# Blog OS (Heap Allocation)
+# Blog OS (VGA Text Mode)

-[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-10)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-10)
+[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-03)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-03)

-This repository contains the source code for the [Heap Allocation][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.
+This repository contains the source code for the [VGA Text Mode][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.

-[post]: https://os.phil-opp.com/heap-allocation/
+[post]: https://os.phil-opp.com/vga-text-mode/

 **Check out the [master branch](https://github.com/phil-opp/blog_os) for more information.**

@@ -56,10 +56,6 @@ dd if=target/x86_64-blog_os/debug/bootimage-blog_os.bin of=/dev/sdX && sync

 Where `sdX` is the device name of your USB stick. **Be careful** to choose the correct device name, because everything on that device is overwritten.

-## Testing
-
-To run the unit and integration tests, execute `cargo xtest`.
-
 ## License

 Licensed under either of
--- a/src/allocator.rs
+++ b/src/allocator.rs
@@ -1,54 +0,0 @@
-use alloc::alloc::{GlobalAlloc, Layout};
-use core::ptr::null_mut;
-use linked_list_allocator::LockedHeap;
-use x86_64::{
-    VirtAddr,
-    structures::paging::{
-        FrameAllocator, Mapper, Page, PageTableFlags, Size4KiB, mapper::MapToError,
-    },
-};
-
-pub const HEAP_START: usize = 0x_4444_4444_0000;
-pub const HEAP_SIZE: usize = 100 * 1024; // 100 KiB
-
-#[global_allocator]
-static ALLOCATOR: LockedHeap = LockedHeap::empty();
-
-pub fn init_heap(
-    mapper: &mut impl Mapper<Size4KiB>,
-    frame_allocator: &mut impl FrameAllocator<Size4KiB>,
-) -> Result<(), MapToError<Size4KiB>> {
-    let page_range = {
-        let heap_start = VirtAddr::new(HEAP_START as u64);
-        let heap_end = heap_start + HEAP_SIZE - 1u64;
-        let heap_start_page = Page::containing_address(heap_start);
-        let heap_end_page = Page::containing_address(heap_end);
-        Page::range_inclusive(heap_start_page, heap_end_page)
-    };
-
-    for page in page_range {
-        let frame = frame_allocator
-            .allocate_frame()
-            .ok_or(MapToError::FrameAllocationFailed)?;
-        let flags = PageTableFlags::PRESENT | PageTableFlags::WRITABLE;
-        unsafe { mapper.map_to(page, frame, flags, frame_allocator)?.flush() };
-    }
-
-    unsafe {
-        ALLOCATOR.lock().init(HEAP_START, HEAP_SIZE);
-    }
-
-    Ok(())
-}
-
-pub struct Dummy;
-
-unsafe impl GlobalAlloc for Dummy {
-    unsafe fn alloc(&self, _layout: Layout) -> *mut u8 {
-        null_mut()
-    }
-
-    unsafe fn dealloc(&self, _ptr: *mut u8, _layout: Layout) {
-        panic!("dealloc should be never called")
-    }
-}
--- a/src/gdt.rs
+++ b/src/gdt.rs
@@ -1,52 +0,0 @@
-use lazy_static::lazy_static;
-use x86_64::VirtAddr;
-use x86_64::structures::gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector};
-use x86_64::structures::tss::TaskStateSegment;
-
-pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
-
-lazy_static! {
-    static ref TSS: TaskStateSegment = {
-        let mut tss = TaskStateSegment::new();
-        tss.interrupt_stack_table[DOUBLE_FAULT_IST_INDEX as usize] = {
-            const STACK_SIZE: usize = 4096 * 5;
-            static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
-
-            let stack_start = VirtAddr::from_ptr(&raw const STACK);
-            let stack_end = stack_start + STACK_SIZE;
-            stack_end
-        };
-        tss
-    };
-}
-
-lazy_static! {
-    static ref GDT: (GlobalDescriptorTable, Selectors) = {
-        let mut gdt = GlobalDescriptorTable::new();
-        let code_selector = gdt.add_entry(Descriptor::kernel_code_segment());
-        let tss_selector = gdt.add_entry(Descriptor::tss_segment(&TSS));
-        (
-            gdt,
-            Selectors {
-                code_selector,
-                tss_selector,
-            },
-        )
-    };
-}
-
-struct Selectors {
-    code_selector: SegmentSelector,
-    tss_selector: SegmentSelector,
-}
-
-pub fn init() {
-    use x86_64::instructions::segmentation::{CS, Segment};
-    use x86_64::instructions::tables::load_tss;
-
-    GDT.0.load();
-    unsafe {
-        CS::set_reg(GDT.1.code_selector);
-        load_tss(GDT.1.tss_selector);
-    }
-}
--- a/src/interrupts.rs
+++ b/src/interrupts.rs
@@ -1,119 +0,0 @@
-use crate::{gdt, hlt_loop, print, println};
-use lazy_static::lazy_static;
-use pic8259::ChainedPics;
-use spin;
-use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame, PageFaultErrorCode};
-
-pub const PIC_1_OFFSET: u8 = 32;
-pub const PIC_2_OFFSET: u8 = PIC_1_OFFSET + 8;
-
-#[derive(Debug, Clone, Copy)]
-#[repr(u8)]
-pub enum InterruptIndex {
-    Timer = PIC_1_OFFSET,
-    Keyboard,
-}
-
-impl InterruptIndex {
-    fn as_u8(self) -> u8 {
-        self as u8
-    }
-
-    fn as_usize(self) -> usize {
-        usize::from(self.as_u8())
-    }
-}
-
-pub static PICS: spin::Mutex<ChainedPics> =
-    spin::Mutex::new(unsafe { ChainedPics::new(PIC_1_OFFSET, PIC_2_OFFSET) });
-
-lazy_static! {
-    static ref IDT: InterruptDescriptorTable = {
-        let mut idt = InterruptDescriptorTable::new();
-        idt.breakpoint.set_handler_fn(breakpoint_handler);
-        idt.page_fault.set_handler_fn(page_fault_handler);
-        unsafe {
-            idt.double_fault
-                .set_handler_fn(double_fault_handler)
-                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX);
-        }
-        idt[InterruptIndex::Timer.as_usize()].set_handler_fn(timer_interrupt_handler);
-        idt[InterruptIndex::Keyboard.as_usize()].set_handler_fn(keyboard_interrupt_handler);
-        idt
-    };
-}
-
-pub fn init_idt() {
-    IDT.load();
-}
-
-extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
-    println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
-}
-
-extern "x86-interrupt" fn page_fault_handler(
-    stack_frame: InterruptStackFrame,
-    error_code: PageFaultErrorCode,
-) {
-    use x86_64::registers::control::Cr2;
-
-    println!("EXCEPTION: PAGE FAULT");
-    println!("Accessed Address: {:?}", Cr2::read());
-    println!("Error Code: {:?}", error_code);
-    println!("{:#?}", stack_frame);
-    hlt_loop();
-}
-
-extern "x86-interrupt" fn double_fault_handler(
-    stack_frame: InterruptStackFrame,
-    _error_code: u64,
-) -> ! {
-    panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
-}
-
-extern "x86-interrupt" fn timer_interrupt_handler(_stack_frame: InterruptStackFrame) {
-    print!(".");
-    unsafe {
-        PICS.lock()
-            .notify_end_of_interrupt(InterruptIndex::Timer.as_u8());
-    }
-}
-
-extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: InterruptStackFrame) {
-    use pc_keyboard::{DecodedKey, HandleControl, Keyboard, ScancodeSet1, layouts};
-    use spin::Mutex;
-    use x86_64::instructions::port::Port;
-
-    lazy_static! {
-        static ref KEYBOARD: Mutex<Keyboard<layouts::Us104Key, ScancodeSet1>> =
-            Mutex::new(Keyboard::new(
-                ScancodeSet1::new(),
-                layouts::Us104Key,
-                HandleControl::Ignore
-            ));
-    }
-
-    let mut keyboard = KEYBOARD.lock();
-    let mut port = Port::new(0x60);
-
-    let scancode: u8 = unsafe { port.read() };
-    if let Ok(Some(key_event)) = keyboard.add_byte(scancode) {
-        if let Some(key) = keyboard.process_keyevent(key_event) {
-            match key {
-                DecodedKey::Unicode(character) => print!("{}", character),
-                DecodedKey::RawKey(key) => print!("{:?}", key),
-            }
-        }
-    }
-
-    unsafe {
-        PICS.lock()
-            .notify_end_of_interrupt(InterruptIndex::Keyboard.as_u8());
-    }
-}
-
-#[test_case]
-fn test_breakpoint_exception() {
-    // invoke a breakpoint exception
-    x86_64::instructions::interrupts::int3();
-}
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,94 +0,0 @@
-#![no_std]
-#![cfg_attr(test, no_main)]
-#![feature(custom_test_frameworks)]
-#![feature(abi_x86_interrupt)]
-#![test_runner(crate::test_runner)]
-#![reexport_test_harness_main = "test_main"]
-
-extern crate alloc;
-use core::panic::PanicInfo;
-
-pub mod allocator;
-pub mod gdt;
-pub mod interrupts;
-pub mod memory;
-pub mod serial;
-pub mod vga_buffer;
-
-pub fn init() {
-    gdt::init();
-    interrupts::init_idt();
-    unsafe { interrupts::PICS.lock().initialize() };
-    x86_64::instructions::interrupts::enable();
-}
-pub trait Testable {
-    fn run(&self) -> ();
-}
-
-impl<T> Testable for T
-where
-    T: Fn(),
-{
-    fn run(&self) {
-        serial_print!("{}...\t", core::any::type_name::<T>());
-        self();
-        serial_println!("[ok]");
-    }
-}
-
-pub fn test_runner(tests: &[&dyn Testable]) {
-    serial_println!("Running {} tests", tests.len());
-    for test in tests {
-        test.run();
-    }
-    exit_qemu(QemuExitCode::Success);
-}
-
-pub fn test_panic_handler(info: &PanicInfo) -> ! {
-    serial_println!("[failed]\n");
-    serial_println!("Error: {}\n", info);
-    exit_qemu(QemuExitCode::Failed);
-    hlt_loop();
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-#[repr(u32)]
-pub enum QemuExitCode {
-    Success = 0x10,
-    Failed = 0x11,
-}
-
-pub fn exit_qemu(exit_code: QemuExitCode) {
-    use x86_64::instructions::port::Port;
-
-    unsafe {
-        let mut port = Port::new(0xf4);
-        port.write(exit_code as u32);
-    }
-}
-
-pub fn hlt_loop() -> ! {
-    loop {
-        x86_64::instructions::hlt();
-    }
-}
-
-#[cfg(test)]
-use bootloader::{BootInfo, entry_point};
-
-#[cfg(test)]
-entry_point!(test_kernel_main);
-
-/// Entry point for `cargo xtest`
-#[cfg(test)]
-fn test_kernel_main(_boot_info: &'static BootInfo) -> ! {
-    init();
-    test_main();
-    hlt_loop();
-}
-
-#[cfg(test)]
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    test_panic_handler(info)
-}
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,78 +1,20 @@
 #![no_std]
 #![no_main]
-#![feature(custom_test_frameworks)]
-#![test_runner(blog_os::test_runner)]
-#![reexport_test_harness_main = "test_main"]

-extern crate alloc;
-
-use alloc::{boxed::Box, rc::Rc, vec, vec::Vec};
-use blog_os::println;
-use bootloader::{BootInfo, entry_point};
 use core::panic::PanicInfo;

-entry_point!(kernel_main);
-
-fn kernel_main(boot_info: &'static BootInfo) -> ! {
-    use blog_os::allocator;
-    use blog_os::memory::{self, BootInfoFrameAllocator};
-    use x86_64::VirtAddr;
+mod vga_buffer;

+#[unsafe(no_mangle)]
+pub extern "C" fn _start() -> ! {
    println!("Hello World{}", "!");
-    blog_os::init();

-    let phys_mem_offset = VirtAddr::new(boot_info.physical_memory_offset);
-    let mut mapper = unsafe { memory::init(phys_mem_offset) };
-    let mut frame_allocator = unsafe { BootInfoFrameAllocator::init(&boot_info.memory_map) };
-
-    allocator::init_heap(&mut mapper, &mut frame_allocator).expect("heap initialization failed");
-
-    // allocate a number on the heap
-    let heap_value = Box::new(41);
-    println!("heap_value at {:p}", heap_value);
-
-    // create a dynamically sized vector
-    let mut vec = Vec::new();
-    for i in 0..500 {
-        vec.push(i);
-    }
-    println!("vec at {:p}", vec.as_slice());
-
-    // create a reference counted vector -> will be freed when count reaches 0
-    let reference_counted = Rc::new(vec![1, 2, 3]);
-    let cloned_reference = reference_counted.clone();
-    println!(
-        "current reference count is {}",
-        Rc::strong_count(&cloned_reference)
-    );
-    core::mem::drop(reference_counted);
-    println!(
-        "reference count is {} now",
-        Rc::strong_count(&cloned_reference)
-    );
-
-    #[cfg(test)]
-    test_main();
-
-    println!("It did not crash!");
-    blog_os::hlt_loop();
+    loop {}
 }

 /// This function is called on panic.
-#[cfg(not(test))]
 #[panic_handler]
 fn panic(info: &PanicInfo) -> ! {
    println!("{}", info);
-    blog_os::hlt_loop();
-}
-
-#[cfg(test)]
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    blog_os::test_panic_handler(info)
-}
-
-#[test_case]
-fn trivial_assertion() {
-    assert_eq!(1, 1);
+    loop {}
 }
--- a/src/memory.rs
+++ b/src/memory.rs
@@ -1,86 +0,0 @@
-use bootloader::bootinfo::{MemoryMap, MemoryRegionType};
-use x86_64::{
-    PhysAddr, VirtAddr,
-    structures::paging::{FrameAllocator, OffsetPageTable, PageTable, PhysFrame, Size4KiB},
-};
-
-/// Initialize a new OffsetPageTable.
-///
-/// This function is unsafe because the caller must guarantee that the
-/// complete physical memory is mapped to virtual memory at the passed
-/// `physical_memory_offset`. Also, this function must be only called once
-/// to avoid aliasing `&mut` references (which is undefined behavior).
-pub unsafe fn init(physical_memory_offset: VirtAddr) -> OffsetPageTable<'static> {
-    unsafe {
-        let level_4_table = active_level_4_table(physical_memory_offset);
-        OffsetPageTable::new(level_4_table, physical_memory_offset)
-    }
-}
-
-/// Returns a mutable reference to the active level 4 table.
-///
-/// This function is unsafe because the caller must guarantee that the
-/// complete physical memory is mapped to virtual memory at the passed
-/// `physical_memory_offset`. Also, this function must be only called once
-/// to avoid aliasing `&mut` references (which is undefined behavior).
-unsafe fn active_level_4_table(physical_memory_offset: VirtAddr) -> &'static mut PageTable {
-    use x86_64::registers::control::Cr3;
-
-    let (level_4_table_frame, _) = Cr3::read();
-
-    let phys = level_4_table_frame.start_address();
-    let virt = physical_memory_offset + phys.as_u64();
-    let page_table_ptr: *mut PageTable = virt.as_mut_ptr();
-
-    unsafe { &mut *page_table_ptr }
-}
-
-/// A FrameAllocator that always returns `None`.
-pub struct EmptyFrameAllocator;
-
-unsafe impl FrameAllocator<Size4KiB> for EmptyFrameAllocator {
-    fn allocate_frame(&mut self) -> Option<PhysFrame> {
-        None
-    }
-}
-
-/// A FrameAllocator that returns usable frames from the bootloader's memory map.
-pub struct BootInfoFrameAllocator {
-    memory_map: &'static MemoryMap,
-    next: usize,
-}
-
-impl BootInfoFrameAllocator {
-    /// Create a FrameAllocator from the passed memory map.
-    ///
-    /// This function is unsafe because the caller must guarantee that the passed
-    /// memory map is valid. The main requirement is that all frames that are marked
-    /// as `USABLE` in it are really unused.
-    pub unsafe fn init(memory_map: &'static MemoryMap) -> Self {
-        BootInfoFrameAllocator {
-            memory_map,
-            next: 0,
-        }
-    }
-
-    /// Returns an iterator over the usable frames specified in the memory map.
-    fn usable_frames(&self) -> impl Iterator<Item = PhysFrame> {
-        // get usable regions from memory map
-        let regions = self.memory_map.iter();
-        let usable_regions = regions.filter(|r| r.region_type == MemoryRegionType::Usable);
-        // map each region to its address range
-        let addr_ranges = usable_regions.map(|r| r.range.start_addr()..r.range.end_addr());
-        // transform to an iterator of frame start addresses
-        let frame_addresses = addr_ranges.flat_map(|r| r.step_by(4096));
-        // create `PhysFrame` types from the start addresses
-        frame_addresses.map(|addr| PhysFrame::containing_address(PhysAddr::new(addr)))
-    }
-}
-
-unsafe impl FrameAllocator<Size4KiB> for BootInfoFrameAllocator {
-    fn allocate_frame(&mut self) -> Option<PhysFrame> {
-        let frame = self.usable_frames().nth(self.next);
-        self.next += 1;
-        frame
-    }
-}
--- a/src/serial.rs
+++ b/src/serial.rs
@@ -1,41 +0,0 @@
-use lazy_static::lazy_static;
-use spin::Mutex;
-use uart_16550::SerialPort;
-
-lazy_static! {
-    pub static ref SERIAL1: Mutex<SerialPort> = {
-        let mut serial_port = unsafe { SerialPort::new(0x3F8) };
-        serial_port.init();
-        Mutex::new(serial_port)
-    };
-}
-
-#[doc(hidden)]
-pub fn _print(args: ::core::fmt::Arguments) {
-    use core::fmt::Write;
-    use x86_64::instructions::interrupts;
-
-    interrupts::without_interrupts(|| {
-        SERIAL1
-            .lock()
-            .write_fmt(args)
-            .expect("Printing to serial failed");
-    });
-}
-
-/// Prints to the host through the serial interface.
-#[macro_export]
-macro_rules! serial_print {
-    ($($arg:tt)*) => {
-        $crate::serial::_print(format_args!($($arg)*));
-    };
-}
-
-/// Prints to the host through the serial interface, appending a newline.
-#[macro_export]
-macro_rules! serial_println {
-    () => ($crate::serial_print!("\n"));
-    ($fmt:expr) => ($crate::serial_print!(concat!($fmt, "\n")));
-    ($fmt:expr, $($arg:tt)*) => ($crate::serial_print!(
-        concat!($fmt, "\n"), $($arg)*));
-}
--- a/src/vga_buffer.rs
+++ b/src/vga_buffer.rs
@@ -163,42 +163,9 @@ macro_rules! println {
    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
 }

-/// Prints the given formatted string to the VGA text buffer
-/// through the global `WRITER` instance.
+/// Prints the given formatted string to the VGA text buffer through the global `WRITER` instance.
 #[doc(hidden)]
 pub fn _print(args: fmt::Arguments) {
    use core::fmt::Write;
-    use x86_64::instructions::interrupts;
-
-    interrupts::without_interrupts(|| {
-        WRITER.lock().write_fmt(args).unwrap();
-    });
-}
-
-#[test_case]
-fn test_println_simple() {
-    println!("test_println_simple output");
-}
-
-#[test_case]
-fn test_println_many() {
-    for _ in 0..200 {
-        println!("test_println_many output");
-    }
-}
-
-#[test_case]
-fn test_println_output() {
-    use core::fmt::Write;
-    use x86_64::instructions::interrupts;
-
-    let s = "Some test string that fits on a single line";
-    interrupts::without_interrupts(|| {
-        let mut writer = WRITER.lock();
-        writeln!(writer, "\n{}", s).expect("writeln failed");
-        for (i, c) in s.chars().enumerate() {
-            let screen_char = writer.buffer.chars[BUFFER_HEIGHT - 2][i].read();
-            assert_eq!(char::from(screen_char.ascii_character), c);
-        }
-    });
+    WRITER.lock().write_fmt(args).unwrap();
 }
--- a/tests/basic_boot.rs
+++ b/tests/basic_boot.rs
@@ -1,25 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(custom_test_frameworks)]
-#![test_runner(blog_os::test_runner)]
-#![reexport_test_harness_main = "test_main"]
-
-use blog_os::println;
-use core::panic::PanicInfo;
-
-#[unsafe(no_mangle)] // don't mangle the name of this function
-pub extern "C" fn _start() -> ! {
-    test_main();
-
-    loop {}
-}
-
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    blog_os::test_panic_handler(info)
-}
-
-#[test_case]
-fn test_println() {
-    println!("test_println output");
-}
--- a/tests/heap_allocation.rs
+++ b/tests/heap_allocation.rs
@@ -1,60 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(custom_test_frameworks)]
-#![test_runner(blog_os::test_runner)]
-#![reexport_test_harness_main = "test_main"]
-
-extern crate alloc;
-
-use alloc::{boxed::Box, vec::Vec};
-use blog_os::allocator::HEAP_SIZE;
-use bootloader::{BootInfo, entry_point};
-use core::panic::PanicInfo;
-
-entry_point!(main);
-
-fn main(boot_info: &'static BootInfo) -> ! {
-    use blog_os::allocator;
-    use blog_os::memory::{self, BootInfoFrameAllocator};
-    use x86_64::VirtAddr;
-
-    blog_os::init();
-    let phys_mem_offset = VirtAddr::new(boot_info.physical_memory_offset);
-    let mut mapper = unsafe { memory::init(phys_mem_offset) };
-    let mut frame_allocator = unsafe { BootInfoFrameAllocator::init(&boot_info.memory_map) };
-    allocator::init_heap(&mut mapper, &mut frame_allocator).expect("heap initialization failed");
-
-    test_main();
-    loop {}
-}
-
-#[test_case]
-fn simple_allocation() {
-    let heap_value_1 = Box::new(41);
-    let heap_value_2 = Box::new(13);
-    assert_eq!(*heap_value_1, 41);
-    assert_eq!(*heap_value_2, 13);
-}
-
-#[test_case]
-fn large_vec() {
-    let n = 1000;
-    let mut vec = Vec::new();
-    for i in 0..n {
-        vec.push(i);
-    }
-    assert_eq!(vec.iter().sum::<u64>(), (n - 1) * n / 2);
-}
-
-#[test_case]
-fn many_boxes() {
-    for i in 0..HEAP_SIZE {
-        let x = Box::new(i);
-        assert_eq!(*x, i);
-    }
-}
-
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    blog_os::test_panic_handler(info)
-}
--- a/tests/should_panic.rs
+++ b/tests/should_panic.rs
@@ -1,25 +0,0 @@
-#![no_std]
-#![no_main]
-
-use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
-use core::panic::PanicInfo;
-
-#[unsafe(no_mangle)]
-pub extern "C" fn _start() -> ! {
-    should_fail();
-    serial_println!("[test did not panic]");
-    exit_qemu(QemuExitCode::Failed);
-    loop {}
-}
-
-fn should_fail() {
-    serial_print!("should_panic::should_fail...\t");
-    assert_eq!(0, 1);
-}
-
-#[panic_handler]
-fn panic(_info: &PanicInfo) -> ! {
-    serial_println!("[ok]");
-    exit_qemu(QemuExitCode::Success);
-    loop {}
-}
--- a/tests/stack_overflow.rs
+++ b/tests/stack_overflow.rs
@@ -1,58 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(abi_x86_interrupt)]
-
-use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
-use core::panic::PanicInfo;
-use lazy_static::lazy_static;
-use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
-
-#[unsafe(no_mangle)]
-pub extern "C" fn _start() -> ! {
-    serial_print!("stack_overflow::stack_overflow...\t");
-
-    blog_os::gdt::init();
-    init_test_idt();
-
-    // trigger a stack overflow
-    stack_overflow();
-
-    panic!("Execution continued after stack overflow");
-}
-
-#[allow(unconditional_recursion)]
-fn stack_overflow() {
-    stack_overflow(); // for each recursion, the return address is pushed
-    volatile::Volatile::new(0).read(); // prevent tail recursion optimizations
-}
-
-lazy_static! {
-    static ref TEST_IDT: InterruptDescriptorTable = {
-        let mut idt = InterruptDescriptorTable::new();
-        unsafe {
-            idt.double_fault
-                .set_handler_fn(test_double_fault_handler)
-                .set_stack_index(blog_os::gdt::DOUBLE_FAULT_IST_INDEX);
-        }
-
-        idt
-    };
-}
-
-pub fn init_test_idt() {
-    TEST_IDT.load();
-}
-
-extern "x86-interrupt" fn test_double_fault_handler(
-    _stack_frame: InterruptStackFrame,
-    _error_code: u64,
-) -> ! {
-    serial_println!("[ok]");
-    exit_qemu(QemuExitCode::Success);
-    loop {}
-}
-
-#[panic_handler]
-fn panic(info: &PanicInfo) -> ! {
-    blog_os::test_panic_handler(info)
-}
--- a/x86_64-blog_os.json
+++ b/x86_64-blog_os.json
@@ -3,7 +3,7 @@
    "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128",
    "arch": "x86_64",
    "target-endian": "little",
-    "target-pointer-width": "64",
+    "target-pointer-width": 64,
    "target-c-int-width": 32,
    "os": "none",
    "executables": true,
Author	SHA1	Message	Date
Philipp Oppermann	93d0daa1e0	Merge branch 'post-02' into post-03	2025-09-03 17:58:28 +02:00
Philipp Oppermann	83e6c0bc00	Merge pull request #1436 from phil-opp/post-02-fix-target Fix: `target-pointer-width` field now expects an integer	2025-09-03 17:56:38 +02:00
Philipp Oppermann	2b11ad8397	Fix: `target-pointer-width` field now expects an integer	2025-09-03 17:53:14 +02:00
Philipp Oppermann	fa51f3adbf	Update to latest bootloader version	2025-09-03 17:52:56 +02:00