basic keyboard support

Makefile

@@ -2,9 +2,10 @@ CXXFLAGS := -m32 -ggdb -g3 -O0 -fno-pic -ffreestanding -fno-rtti -fno-exceptions
 LDFLAGS := -m32 -static -T link.ld -ffreestanding -nostdlib
 
 CXXFILES := acpi.cpp \
-	boot.cpp \
+        boot.cpp \
         gdt.cpp \
         idt.cpp \
+        keyboard.cpp \
         memory.cpp \
         multiboot.cpp \
         pic.cpp \

idt.cpp

@@ -40,8 +40,11 @@ void interruptGeneralHandler(Registers regs)
     }
 
     if (inum < callbacks.size()) {
-       if (auto cb = callbacks[inum]; cb)
-           cb(regs);
+        if (auto cb = callbacks[inum]; cb) {
+            asm volatile("cli");
+            cb(regs);
+            asm volatile("sti");
+        }
     }
 }
 

kernel.cpp

@@ -1,10 +1,12 @@
 #include "acpi.hpp"
 #include "gdt.hpp"
 #include "idt.hpp"
+#include "keyboard.hpp"
 #include "memory.hpp"
 #include "multiboot.hpp"
 #include "pic.hpp"
 #include "pit.hpp"
+#include "portio.hpp"
 #include "tasking.hpp"
 #include "vgaterminal.hpp"
 
@@ -33,39 +35,40 @@ void kernel_main(void)
     pic_initialize();
     idt_initialize();
     pit_initialize();
+    keyboard_initialize();
     asm volatile("sti");
     tasking_initialize();
     term.write("Tasking enabled.\n");
 
-    tasking_spawn([] {
-        for (;;) {
-            do pit_delay_ms(1);
-            while (termBusy);
+    //tasking_spawn([] {
+    //    for (;;) {
+    //        do pit_delay_ms(1);
+    //        while (termBusy);
 
-            termBusy = true;
-            term.write('B');
-            termBusy = false;
-        }
-    }, 256);
+    //        termBusy = true;
+    //        term.write('B');
+    //        termBusy = false;
+    //    }
+    //}, 256);
 
-    tasking_spawn([] {
-        for (;;) {
-            do pit_delay_ms(1);
-            while (termBusy);
+    //tasking_spawn([] {
+    //    for (;;) {
+    //        do pit_delay_ms(1);
+    //        while (termBusy);
 
-            termBusy = true;
-            term.write('C');
-            termBusy = false;
-        }
-    }, 256);
+    //        termBusy = true;
+    //        term.write('C');
+    //        termBusy = false;
+    //    }
+    //}, 256);
 
     for (;;) {
-        do pit_delay_ms(1);
-        while (termBusy);
+        pit_delay_ms(100);
+        //while (termBusy);
 
-        termBusy = true;
-        term.write('A');
-        termBusy = false;
+        //termBusy = true;
+        //term.write('A');
+        //termBusy = false;
     }
 }
 

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);
+        }
+    });
+}
+

keyboard.hpp

@@ -0,0 +1,7 @@
+#ifndef KEYBOARD_HPP
+#define KEYBOARD_HPP
+
+void keyboard_initialize();
+
+#endif // KEYBOARD_HPP
+

vgaterminal.cpp

@@ -8,7 +8,16 @@
 
 void VGATerminal::write(char c) noexcept
 {
+    checkpos();
+
     switch (c) {
+    case '\b':
+        if (offset % Width) {
+            --offset;
+            put(' ');
+            --offset;
+        }
+        break;
     case '\n':
         offset += Width;
         [[fallthrough]];
@@ -16,11 +25,11 @@ void VGATerminal::write(char c) noexcept
         offset -= offset % Width;
         break;
     default:
-        checkpos();
         put(c);
-        updatecursor();
         break;
     }
+
+    updatecursor();
 }
 
 void VGATerminal::put(char c) noexcept