kapi: move platform independent implementation

2 files changed, 77 insertions, 0 deletions

diff --git a/src/kapi/cio.cpp b/src/kapi/cio.cpp
new file mode 100644
index 0000000..66493b6
--- /dev/null
+++ b/src/kapi/cio.cpp
@@ -0,0 +1,57 @@
+#include "kapi/cio.hpp"
+
+#include <optional>
+#include <string_view>
+#include <utility>
+
+namespace teachos::cio
+{
+  namespace
+  {
+    struct null_device final : public output_device
+    {
+      null_device static instance;
+
+      auto write(std::string_view) -> void override {}
+      auto writeln(std::string_view) -> void override {}
+
+      auto write_error(std::string_view) -> void override {}
+      auto writeln_error(std::string_view) -> void override {}
+    };
+
+    constinit null_device null_device::instance;
+  }  // namespace
+
+  // NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
+  constinit auto active_device = static_cast<output_device *>(&null_device::instance);
+
+  auto set_output_device(output_device & device) -> std::optional<output_device *>
+  {
+    if (&device == active_device)
+    {
+      return {};
+    }
+    return std::exchange(active_device, &device);
+  }
+
+  auto print(std::string_view text) -> void
+  {
+    active_device->write(text);
+  }
+
+  auto println(std::string_view text) -> void
+  {
+    active_device->writeln(text);
+  }
+
+  auto print_error(std::string_view text) -> void
+  {
+    active_device->write_error(text);
+  }
+
+  auto println_error(std::string_view text) -> void
+  {
+    active_device->writeln_error(text);
+  }
+
+}  // namespace teachos::cio
\ No newline at end of file
diff --git a/src/kapi/system.cpp b/src/kapi/system.cpp
new file mode 100644
index 0000000..3ae3f29
--- /dev/null
+++ b/src/kapi/system.cpp
@@ -0,0 +1,20 @@
+#include "kapi/system.hpp"
+
+#include "kapi/cio.hpp"
+#include "kapi/cpu.hpp"
+
+namespace teachos::system
+{
+
+  [[gnu::weak]]
+  auto panic(std::string_view message, std::source_location location) -> void
+  {
+    cio::println_error("!!!Kernel Panic!!! ");
+    cio::println_error(message);
+    cio::println_error(location.file_name());
+    cio::println_error(location.function_name());
+
+    cpu::halt();
+  }
+
+}  // namespace teachos::system