From 95f823c2c3ada5f175dc5735886703387263b6f4 Mon Sep 17 00:00:00 2001
From: Arnau478 <arnauxabia@gmail.com>
Date: Mon, 20 Jun 2022 18:05:28 +0200
Subject: [PATCH] PS/2 keyboard lowercase support

---
 src/kernel/drivers/keyboard.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/kernel/drivers/keyboard.c b/src/kernel/drivers/keyboard.c
index 3a52a06..570de1d 100644
--- a/src/kernel/drivers/keyboard.c
+++ b/src/kernel/drivers/keyboard.c
@@ -1,3 +1,4 @@
+#include <stdbool.h>
 #include "../lib/string.h"
 #include "keyboard.h"
 #include "../arch/i686/isr.h"
@@ -6,16 +7,19 @@
 #include "../lib/stdio.h"
 #include "../shell.h"
 
+static bool g_caps_lock = false;
+static bool g_shift = false;
+
 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', ',', '.', '/', '?', '?',
+    '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', ',', '.', '/', '?', '?',
     '?', ' '
 };
 
@@ -25,8 +29,10 @@ static void user_input(char *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 == 0x2A) g_shift = true; // Shift pressed
+    else if(scancode == 0x2A + 128) g_shift = false; // Shift released
+    else if(scancode == 0x3A) g_caps_lock = !g_caps_lock; // Caps lock pressed
+    else 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';
@@ -37,13 +43,15 @@ static void keyboard_callback(){
             g_key_buffer[0] = '\0';
         }
         else{
-            putc(g_sc_ascii[scancode]);
+            char c = g_sc_ascii[scancode];
+            if(c >= 'a' && c <= 'z' && g_shift != g_caps_lock) c += 'A' - 'a';
+            putc(c);
 
             // strlen() works here because char[] is the same as
             // char*, and both are null-terminated, so they are
             // exactly the same
             int len = strlen(g_key_buffer);
-            g_key_buffer[len] = g_sc_ascii[scancode];
+            g_key_buffer[len] = c;
             g_key_buffer[len+1] = '\0';
         }
     }