...

makefile

@@ -6,7 +6,7 @@ CFLAGS 	= -m64 -ffreestanding -fno-builtin -Wall -Wextra -Wshadow -std=c23 -g
 LDFLAGS	= -g
 ASFLAGS	= -f elf64 -g -F dwarf
 
-SRC_C   := src/kernel.c src/string.c src/vga.c src/interrupts.c
+SRC_C   := src/kernel.c src/string.c src/vga.c src/interrupts.c src/keyboard.c
 SRC_ASM := src/start.asm
 
 OBJ_C   := $(SRC_C:src/%.c=.build/%.o)

src/interrupts.c

@@ -100,8 +100,6 @@ void handle_irq(const isr_frame_t* frame)
 
 void handle_isr(const isr_frame_t* frame)
 {
-    kprintf("isr");
-
     if (frame->int_no < 32)
     {
         handle_exception(frame);

src/kernel.c

@@ -1,15 +1,26 @@
 #include "kernel.h"
 #include "interrupts.h"
+#include "keyboard.h"
 #include "string.h"
 #include "vga.h"
 #include <stdarg.h>
 #include <stddef.h>
 
+void handle_keypress(const keyboard_event_t* event)
+{
+    if (event->pressed && event->ascii)
+    {
+        kprintf("%c", event->ascii);
+    }
+}
+
 void kmain()
 {
     vga_clear();
     pic_remap();
     enable_interrupts();
+    init_keyboard();
+    register_keypress_handler(handle_keypress);
 
     kprintf("Welcome to nub OS\n");
     khalt();
@@ -18,6 +29,7 @@ void kmain()
 void kpanic()
 {
     kprintf("Kernel panic!\n");
+    disable_interrupts();
     khalt();
 }
 
@@ -33,6 +45,7 @@ void kprintf(const char* fmt, ...)
         if (should_format)
         {
             should_format = false;
+
             if (fmt[i] == '%')
             {
                 vga_put_char('%', 0x0F);
@@ -45,6 +58,11 @@ void kprintf(const char* fmt, ...)
                     vga_put_char(str[j], 0x0F);
                 }
             }
+            else if (fmt[i] == 'c')
+            {
+                char character = (char)va_arg(args, int64_t);
+                vga_put_char(character, 0x0F);
+            }
             else if (fmt[i] == 'd')
             {
                 int64_t val = va_arg(args, int64_t);
@@ -65,6 +83,10 @@ void kprintf(const char* fmt, ...)
                     vga_put_char(buf[j], 0x0F);
                 }
             }
+            else
+            {
+                vga_put_char(fmt[i], 0x0F);
+            }
         }
         else if (fmt[i] == '%')
         {

src/kernel.h

@@ -6,7 +6,6 @@ static inline void khalt()
 {
     while (true)
     {
-        __asm__ volatile ("cli");
         __asm__ volatile ("hlt");
     }
 }

src/keyboard.c

@@ -3,6 +3,7 @@
 #include "kernel.h"
 #include "vga.h"
 #include "util.h"
+#include <stddef.h>
 
 #define SCANCODE_LEFT_SHIFT 42
 #define SCANCODE_RIGHT_SHIFT 54
@@ -31,7 +32,7 @@ bool caps_lock = false;
 
 // todo(nub): make dynamic when a memory allocator is implemented
 static keyboard_handler_t keyboard_handlers[KEYBOARD_HANDLERS_LENGTH];
-static int handler_index = 0;
+static size_t handler_index = 0;
 
 char scan_code_to_ascii(uint8_t scan_code)
 {

src/vga.c

@@ -35,6 +35,34 @@ void vga_put_char(char character, uint8_t color)
         cursor_col += remainter == 0 ? 4 : remainter;
         break;
     }
+    case '\b':
+    {
+        if (cursor_col > 0)
+        {
+            cursor_col -= 1;
+        }
+        else if (cursor_row > 0)
+        {
+            cursor_row -= 1;
+
+            cursor_col = 0;
+            for (int col = COLUMNS - 1; col >= 0; col--)
+            {
+                vga_char_t cell = vga_buffer[cursor_row * COLUMNS + col];
+                if (cell.character != ' ')
+                {
+                    cursor_col = col;
+                    break;
+                }
+            }
+        }
+
+        vga_buffer[cursor_row * COLUMNS + cursor_col] = (vga_char_t){
+            .character = ' ',
+            .color = VGA_LIGHT_GRAY | VGA_BLACK << 4,
+        };
+        break;
+    }
     default:
     {
         vga_buffer[COLUMNS * cursor_row + cursor_col] = (vga_char_t){