From dc4e6ff31cae52da27da4489cd39488541fbe1ea Mon Sep 17 00:00:00 2001
From: Juozas Vainauskas <71255955+JuozasVainauskas@users.noreply.github.com>
Date: Sun, 3 Dec 2023 13:03:55 +0200
Subject: [PATCH] Handle CPU exceptions (#6)

---
 src/interrupts.rs | 24 ++++++++++++++++++++++++
 src/lib.rs        |  7 +++++++
 src/main.rs       |  3 +++
 3 files changed, 34 insertions(+)
 create mode 100644 src/interrupts.rs

diff --git a/src/interrupts.rs b/src/interrupts.rs
new file mode 100644
index 0000000..dbeae7d
--- /dev/null
+++ b/src/interrupts.rs
@@ -0,0 +1,24 @@
+use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+use crate::println;
+use lazy_static::lazy_static;
+
+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: InterruptStackFrame) {
+    println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
+}
+
+#[test_case]
+fn test_breakpoint_exceptions() {
+    x86_64::instructions::interrupts::int3();
+}
diff --git a/src/lib.rs b/src/lib.rs
index 052452f..4b3b12a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,11 +3,17 @@
 #![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 serial;
 pub mod vga_buffer;
+pub mod interrupts;
+
+pub fn init() {
+    interrupts::init_idt();
+}
 
 pub trait Testable {
     fn run(&self) -> ();
@@ -59,6 +65,7 @@ pub fn exit_qemu(exit_code: QemuExitCode) {
 #[cfg(test)]
 #[no_mangle]
 pub extern "C" fn _start() -> ! {
+    init();
     test_main();
     loop {}
 }
diff --git a/src/main.rs b/src/main.rs
index f7996e4..9ddd14b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -19,6 +19,9 @@ pub extern "C" fn _start() -> ! {
 
     println!("System booted successfully");
 
+    os::init();
+
+    x86_64::instructions::interrupts::int3();
 
     #[cfg(test)]
     test_main();