basic keyboard support

1 files changed, 65 insertions, 0 deletions

diff --git a/keyboard.cpp b/keyboard.cpp
new file mode 100644
index 0000000..18d7acd
--- /dev/null
+++ b/keyboard.cpp
@@ -0,0 +1,65 @@
+#include "idt.hpp"
+#include "portio.hpp"
+#include "vgaterminal.hpp"
+
+#include <array>
+#include <cstdint>
+
+#define K_CONTROL_L -1
+#define K_SHIFT_L   -2
+#define K_ALT_L     -3
+#define K_CAPS      -4
+#define K_NUM       -5
+#define K_SCROLL    -6
+#define K_SHIFT_R   -7
+#define K_ESCAPE    -8
+#define K_F1        -10
+#define K_F2        -11
+#define K_F3        -12
+#define K_F4        -13
+#define K_F5        -14
+#define K_F6        -15
+#define K_F7        -16
+#define K_F8        -17
+#define K_F9        -18
+#define K_F10       -19
+#define K_F11       -20
+#define K_F12       -21
+
+extern TextOutput& term;
+
+static const std::array<char, 0x59> ScanCodeSet1 {{
+    0, K_ESCAPE,
+    '1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
+    '-', '=', '\b', '\t',
+    'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '[', ']', '\n', K_CONTROL_L,
+    'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K', 'L', ';', '\'', '`', K_SHIFT_L, '\\',
+    'Z', 'X', 'C', 'V', 'B', 'N', 'M', ',', '.', '/',
+    K_SHIFT_R, '*', K_ALT_L, ' ', K_CAPS,
+    K_F1, K_F2, K_F3, K_F4, K_F5, K_F6, K_F7, K_F8, K_F9, K_F10,
+    K_NUM, K_SCROLL, '7', '8', '9', '-', '4', '5', '6', '+', '1', '2', '3', '0', '.',
+    0, 0, 0, // non-existant
+    K_F11, K_F12
+}};
+
+static constexpr bool isReleased(auto ch) {
+    return ch & 0x80;
+}
+
+static constexpr auto keycode(auto ch) {
+    return ch & 0x7F;
+}
+
+void keyboard_initialize()
+{
+    idt_register_callback(33, [](auto& regs) {
+        const auto kc = inb(0x60);
+
+        if (!isReleased(kc)) {
+            const auto ch = ScanCodeSet1[keycode(kc)];
+            if (ch > 0)
+                term.write(ch);
+        }
+    });
+}
+