Start handling interrupts, handle breakpoint exceptions

src/interrupts.rs

@@ -0,0 +1,19 @@
+use crate::println;
+use lazy_static::lazy_static;
+use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+
+lazy_static! {
+    static ref IDT: InterruptDescriptorTable = {
+        let mut idt = InterruptDescriptorTable::new();
+        idt.breakpoint.set_handler_fn(breakpoint_handler);
+        idt
+    };
+}
+
+pub fn init_idt() {
+    IDT.load();
+}
+
+extern "x86-interrupt" fn breakpoint_handler(stack_frame: &mut InterruptStackFrame) {
+    println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
+}

src/lib.rs

@@ -3,12 +3,18 @@
 #![feature(custom_test_frameworks)]
 #![test_runner(crate::test_runner)]
 #![reexport_test_harness_main = "test_main"]
+#![feature(abi_x86_interrupt)]
 
 use core::panic::PanicInfo;
 
+pub mod interrupts;
 pub mod serial;
 pub mod vga_buffer;
 
+pub fn init() {
+    interrupts::init_idt();
+}
+
 pub trait Testable {
     fn run(&self) -> ();
 }
@@ -41,10 +47,12 @@ pub fn test_panic_handler(info: &PanicInfo) -> ! {
     exit_qemu(QemuExitCode::Failed);
     loop {}
 }
+
 /// Entry point for `cargo test`
 #[cfg(test)]
 #[no_mangle]
 pub extern "C" fn _start() -> ! {
+    init();
     test_main();
     loop {}
 }
@@ -70,3 +78,9 @@ pub fn exit_qemu(exit_code: QemuExitCode) {
         port.write(exit_code as u32);
     }
 }
+
+#[test_case]
+fn test_breakpoint_exception() {
+    // invoke a breakpoint exception
+    x86_64::instructions::interrupts::int3();
+}

src/main.rs

@@ -13,9 +13,16 @@ pub extern "C" fn _start() -> ! {
 
     println!("k_os minimal kernel successfully boot loaded!");
 
+    k_os::init();
+
+    // invoke a breakpoint exception
+    x86_64::instructions::interrupts::int3(); // new
+
     #[cfg(test)]
     test_main();
 
+    println!("It did not crash!");
+
     loop {}
 }