PS/2 keyboard driver

src/kernel/drivers/keyboard.c

@@ -0,0 +1,51 @@
+#include "../util/string.h"
+#include "keyboard.h"
+#include "../arch/i686/isr.h"
+#include "../stdio.h"
+#include "../arch/i686/io.h"
+#include "../stdio.h"
+
+static char g_key_buffer[256];
+
+static const char g_sc_ascii[128] = {
+    '?', '?', '1', '2', '3', '4', '5', '6',
+    '7', '8', '9', '0', '-', '=', '?', '?',
+    'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I',
+    'O', 'P', '[', ']', '?', '?', 'A', 'S',
+    'D', 'F', 'G', 'H', 'J', 'K', 'L', ';',
+    '\'', '`', '?', '\\', 'z', 'x', 'c', 'v',
+    'B', 'N', 'M', ',', '.', '/', '?', '?',
+    '?', ' '
+};
+
+static void user_input(char *str){
+    printf("In: \"%s\"\n", str);
+}
+
+static void keyboard_callback(){
+    uint8_t scancode = i686_inb(0x60);
+    //printf("KEYBOARD (%i)!\n", scancode);
+    if(scancode < 128){ // If it's a "pressed" event, not "released"
+        if(scancode == 0x0E){ // Backspace
+            putc('\b');
+            g_key_buffer[strlen(g_key_buffer)-1] = '\0';
+        }
+        else if(scancode == 0x1C){ // Enter
+            putc('\n');
+            user_input(g_key_buffer);
+            g_key_buffer[0] = '\0';
+        }
+        else{
+            putc(g_sc_ascii[scancode]);
+
+            // strlen() works here because char[] is the same as
+            // char*, and both are null-terminated, so they are
+            // exactly the same
+            g_key_buffer[strlen(g_key_buffer)] = g_sc_ascii[scancode];
+        }
+    }
+}
+
+void keyboard_initialize(){
+    i686_isr_register_handler(IRQ(1), keyboard_callback);
+}

src/kernel/drivers/keyboard.h

@@ -0,0 +1,3 @@
+#pragma once
+
+void keyboard_initialize();

src/kernel/drivers/timer.c

@@ -3,7 +3,7 @@
 #include "../stdio.h"
 
 static void timer_handler(registers *regs){
-    printf("TICK\n");
+    //printf("TICK\n");
 }
 
 void timer_initialize(){

src/kernel/drivers/vga.c

@@ -50,8 +50,11 @@ int vga_print_char(char c, int x, int y){
         offset = (y+1)*VGA_WIDTH;
     }
     else if(c == '\b'){
-        VGA_MEMORY[offset*2] = ' ';
-        VGA_MEMORY[offset*2+1] = current_color;
+        if(offset != 0){
+            offset--;
+            VGA_MEMORY[offset*2] = ' ';
+            VGA_MEMORY[offset*2+1] = current_color;
+        }
     }
     else{
         VGA_MEMORY[offset*2] = c;
@@ -115,3 +118,12 @@ void vga_print_string_at(char *str, int x, int y){
 void vga_print_string(char *str){
     vga_print_string_at(str, -1, -1);
 }
+
+void vga_fill_screen(char c, uint8_t color){
+    for(int y = 0; y < VGA_HEIGHT; y++){
+        for(int x = 0; x < VGA_WIDTH; x++){
+            vga_set_char(x, y, c);
+            vga_set_color(x, y, color);
+        }
+    }
+}

src/kernel/drivers/vga.h

@@ -53,3 +53,4 @@ int vga_get_cursor();
 int vga_print_char(char c, int x, int y);
 void vga_print_string_at(char *str, int x, int y);
 void vga_print_string(char *str);
+void vga_fill_screen(char c, uint8_t color);

src/kernel/main.c

@@ -2,13 +2,13 @@
 #include "stdio.h"
 #include "hal/hal.h"
 #include "drivers/timer.h"
+#include "drivers/keyboard.h"
 
 void __attribute__((cdecl)) kmain(uint64_t magic, uint64_t addr){
     hal_initialize();
     timer_initialize();
+    keyboard_initialize();
     
-    puts("\x1b[33mWARNING\x1b[0m");
-    printf(": amazing %s ahead!\n", "math");
-    printf("%i+%i=%i\n", 1, 1, 2);
+    clear_screen();
     for(;;);
 }

src/kernel/stdio.c

@@ -101,3 +101,8 @@ void printf(char *fmt, ...){
         else putc(*(fmt++));
     }
 }
+
+void clear_screen(){
+    vga_fill_screen(' ', VGA_COLOR_BG_BLACK | VGA_COLOR_FG_WHITE);
+    vga_set_cursor(0);
+}

src/kernel/stdio.h

@@ -3,3 +3,4 @@
 void puts(char *str);
 void putc(char c);
 void printf(char *fmt, ...);
+void clear_screen();

src/kernel/util/string.c

@@ -0,0 +1,7 @@
+#include "string.h"
+
+int strlen(char *s){
+    int len = 0;
+    while(*(s++)) len++;
+    return len;
+}

src/kernel/util/string.h

@@ -0,0 +1,3 @@
+#pragma once
+
+int strlen(char *s);