os: rework kernel architecture

Rework the code structure and architecture of the kernel by separating
platform-dependent and platform-independent code more cleanly. As of
this patchset, full feature parity has not been achieved. Nonetheless, a
sufficient subset of functionality has been ported to the new
architecture to demonstrate the feasibility of the new structure.

1 files changed, 71 insertions, 0 deletions

diff --git a/arch/x86_64/pre/src/kernel/main.cpp b/arch/x86_64/pre/src/kernel/main.cpp
new file mode 100644
index 0000000..43b5f90
--- /dev/null
+++ b/arch/x86_64/pre/src/kernel/main.cpp
@@ -0,0 +1,71 @@
+#include "arch/kernel/main.hpp"
+
+#include "arch/boot/pointers.hpp"
+#include "arch/context_switching/interrupt_descriptor_table/segment_selector.hpp"
+#include "arch/context_switching/main.hpp"
+#include "arch/kernel/cpu/if.hpp"
+#include "arch/kernel/cpu/segment_register.hpp"
+#include "arch/memory/heap/bump_allocator.hpp"
+#include "arch/memory/heap/global_heap_allocator.hpp"
+#include "arch/memory/main.hpp"
+#include "arch/memory/multiboot/reader.hpp"
+#include "arch/stl/vector.hpp"
+#include "arch/video/vga/text.hpp"
+
+namespace teachos::arch::kernel
+{
+  auto stack_overflow_test(int count) -> int
+  {
+    int test[5000] = {};
+    if (test[0] == 0xFFFF)
+    {
+      return count;
+    }
+    count = stack_overflow_test(count);
+    return count++;
+  }
+
+  auto heap_test() -> void
+  {
+    auto test2 = new memory::multiboot::memory_information{};
+    auto test3 = new memory::multiboot::memory_information{};
+    auto test4 = *test2;
+    auto test5 = *test3;
+    test4.kernel_end = 5000;
+    test5.kernel_end = 3000;
+    auto test6 = test4.kernel_end;
+    auto test7 = test5.kernel_end;
+    auto test8 = memory::multiboot::read_multiboot2();
+    if (test6 && test7 && test8.kernel_end)
+    {
+      video::vga::text::write("Heap test successful", video::vga::text::common_attributes::green_on_black);
+    }
+    test2->kernel_end = 2000;
+    test2->kernel_start = 1000;
+    test2->multiboot_start = 2000;
+    delete test2;
+    delete test3;
+
+    auto test9 = new int(50);
+    delete test9;
+  }
+
+  auto main() -> void
+  {
+    video::vga::text::clear();
+    video::vga::text::cursor(false);
+    video::vga::text::write("TeachOS is starting up...", video::vga::text::common_attributes::green_on_black);
+    video::vga::text::newline();
+
+    memory::initialize_memory_management();
+    // stack_overflow_test(0);
+
+    memory::heap::global_heap_allocator::register_heap_allocator(memory::heap::heap_allocator_type::LINKED_LIST);
+    // heap_test();
+
+    auto address = memory::heap::global_heap_allocator::kmalloc(8U);
+    (void)address;
+
+    context_switching::switch_to_user_mode();
+  }
+}  // namespace teachos::arch::kernel