From d8ddd93832f55b5f263002ed5d7376ca3fa21d13 Mon Sep 17 00:00:00 2001
From: Tom-on64 <kubecekt@gmail.com>
Date: Tue, 12 Mar 2024 16:13:24 +0100
Subject: [PATCH] Started working on disk.h header

---
 src/boot.asm         | 4 +++-
 src/kernel/disk.c    | 1 +
 src/kernel/disk.h    | 8 ++++++++
 src/kernel/entry.asm | 5 +++++
 src/kernel/main.c    | 5 +++++
 5 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 src/kernel/disk.c
 create mode 100644 src/kernel/disk.h

diff --git a/src/boot.asm b/src/boot.asm
index 227c76a..7e793fc 100644
--- a/src/boot.asm
+++ b/src/boot.asm
@@ -88,7 +88,7 @@ puts:
     ret
 
 ;; Data
-driveNum: db 3
+driveNum: db 0
 counter: db 0
 cursor: dw 0
 
@@ -112,6 +112,8 @@ protected_start:
     mov esp, ebp
 
     ; Perform the far jump
+    mov al, [driveNum]
+    push ax
     jmp KERNEL_LOC
     
 ;; GDT
diff --git a/src/kernel/disk.c b/src/kernel/disk.c
new file mode 100644
index 0000000..f7ba18f
--- /dev/null
+++ b/src/kernel/disk.c
@@ -0,0 +1 @@
+#include "disk.h"
diff --git a/src/kernel/disk.h b/src/kernel/disk.h
new file mode 100644
index 0000000..b23ec64
--- /dev/null
+++ b/src/kernel/disk.h
@@ -0,0 +1,8 @@
+#ifndef DISK_H
+#define DISK_H
+
+#include "stdint.h"
+
+extern uint8_t driveNum;
+
+#endif
diff --git a/src/kernel/entry.asm b/src/kernel/entry.asm
index dfb276b..c804803 100644
--- a/src/kernel/entry.asm
+++ b/src/kernel/entry.asm
@@ -8,9 +8,14 @@
 
 ;; Calls the main function in 'main.c'
 _start:
+    pop ax
+    mov [driveNum], al
     call main
     jmp $       ;; If we used cli, hlt we wouldn't have interrupts :/
 
+[global driveNum]
+driveNum: db 0
+
 ;;
 ;; --- IDT ---
 ;;
diff --git a/src/kernel/main.c b/src/kernel/main.c
index ad48db1..ac8d27b 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -5,6 +5,8 @@
 #include "keyboard.h"
 #include "timer.h"
 #include "system.h"
+#include "disk.h"
+#include "string.h"
 
 void main() {
     // Interrupts
@@ -20,5 +22,8 @@ void main() {
 
     clear(0x0f);
     print("kern.\n\n", 0x0f);
+    print("Drive: 0x", 0x0f);
+    print(itoa(driveNum, 16), 0x0f);
+    putc('\n', 0x00);
 }