From c5a39e09024abc21ef89e61209a5e341a56518d0 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Thu, 25 Apr 2019 18:30:49 +0200
Subject: [PATCH] Add a stack overflow integration test

---
 tests/stack_overflow.rs | 64 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 tests/stack_overflow.rs

diff --git a/tests/stack_overflow.rs b/tests/stack_overflow.rs
new file mode 100644
index 00000000..14ad16a6
--- /dev/null
+++ b/tests/stack_overflow.rs
@@ -0,0 +1,64 @@
+#![no_std]
+#![no_main]
+#![feature(abi_x86_interrupt)]
+
+use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use core::panic::PanicInfo;
+use lazy_static::lazy_static;
+
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    serial_print!("stack_overflow... ");
+
+    blog_os::gdt::init();
+    init_test_idt();
+
+    // trigger a stack overflow
+    stack_overflow();
+
+    serial_println!("[failed]");
+    serial_println!("Execution continued after stack overflow");
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+#[allow(unconditional_recursion)]
+fn stack_overflow() {
+    stack_overflow(); // for each recursion, the return address is pushed
+}
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    serial_println!("[failed]");
+    serial_println!("{}", info);
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+
+lazy_static! {
+    static ref TEST_IDT: InterruptDescriptorTable = {
+        let mut idt = InterruptDescriptorTable::new();
+        unsafe {
+            idt.double_fault
+                .set_handler_fn(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 double_fault_handler(
+    _stack_frame: &mut InterruptStackFrame,
+    _error_code: u64,
+) {
+    serial_println!("[ok]");
+    exit_qemu(QemuExitCode::Success);
+    loop {}
+}