x86_64/vga: extract buffer type

1 files changed, 60 insertions, 0 deletions

diff --git a/arch/x86_64/src/vga/text/device.cpp b/arch/x86_64/src/vga/text/device.cpp
new file mode 100644
index 0000000..2da9e06
--- /dev/null
+++ b/arch/x86_64/src/vga/text/device.cpp
@@ -0,0 +1,60 @@
+#include "kapi/cio.hpp"
+
+#include "x86_64/boot/boot.hpp"
+#include "x86_64/boot/ld.hpp"
+#include "x86_64/vga/crtc.hpp"
+#include "x86_64/vga/text.hpp"
+
+#include <bit>
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+
+namespace teachos::vga::x86_64::text
+{
+  namespace
+  {
+    constexpr auto default_buffer_address = std::uintptr_t{0xb8000};
+    constexpr auto default_buffer_width = 80z;
+    constexpr auto default_buffer_height = 25z;
+
+    constexpr auto bit_cursor_enabled = 5U;
+  }  // namespace
+
+  device::device()
+      : m_buffer{default_buffer_width, default_buffer_height,
+                 std::bit_cast<buffer::cell *>(default_buffer_address +
+                                               std::bit_cast<std::uintptr_t>(&teachos::boot::x86_64::TEACHOS_VMA)),
+                 boot::bootstrap_information.vga_buffer_index}
+  {
+    clear();
+  }
+
+  auto device::clear() -> void
+  {
+    m_buffer.clear();
+  }
+
+  auto device::cursor(bool enabled) -> void
+  {
+    auto cursor_disable_byte = std::byte{!enabled} << bit_cursor_enabled;
+
+    crtc::address::write(crtc::registers::cursor_start);
+    crtc::data::write(crtc::data::read() | cursor_disable_byte);
+  }
+
+  auto device::write(cio::output_stream stream, std::string_view text) -> void
+  {
+    auto attributes = [&] -> attribute {
+      switch (stream)
+      {
+        case cio::output_stream::stderr:
+          return red_on_black;
+        default:
+          return green_on_black;
+      }
+    }();
+    m_buffer.write(text, attributes);
+  }
+
+}  // namespace teachos::vga::x86_64::text