#![no_std]
#![no_main]
#![feature(custom_test_frameworks)]
#![test_runner(rustos::test_runner)]
#![reexport_test_harness_main = "test_main"]
#![feature(abi_x86_interrupt)]
extern crate rustos;
use core::panic::PanicInfo;
use rustos::println;
#[no_mangle]
pub extern "C" fn _start() -> ! {
println!("Welcome to the real world!");
init();
#[cfg(not(test))]
stack_overflow();
#[cfg(test)]
test_main();
println!("It did not crash!!!");
loop {}
}
#[cfg(not(test))]
#[allow(unconditional_recursion)]
fn stack_overflow() {
stack_overflow();
}
#[cfg(not(test))]
#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
println!("{}", info);
loop {}
}
#[cfg(test)]
#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
rustos::test_panic_handler(info)
}
extern crate lazy_static;
extern crate x86_64;
use lazy_static::lazy_static;
#[allow(unused_imports)]
use x86_64::{
structures::{
gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector},
idt::{InterruptDescriptorTable, InterruptStackFrame},
tss::TaskStateSegment,
},
VirtAddr,
};
pub fn init() {
use x86_64::instructions::segmentation::set_cs;
use x86_64::instructions::tables::load_tss;
GDT.0.load();
unsafe {
set_cs(GDT.1.code_selector);
load_tss(GDT.1.tss_selector);
}
IDT.load();
}
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,
}
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;
static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
let stack_start = VirtAddr::from_ptr(unsafe { &STACK });
stack_start + STACK_SIZE
};
tss
};
}
lazy_static! {
static ref IDT: InterruptDescriptorTable = {
let mut idt = InterruptDescriptorTable::new();
unsafe {
idt.double_fault
.set_handler_fn(double_fault_handler)
.set_stack_index(DOUBLE_FAULT_IST_INDEX);
}
idt
};
}
extern "x86-interrupt" fn double_fault_handler(
stack_frame: &mut InterruptStackFrame,
_error_code: u64,
) -> ! {
panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
}