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Code: Select all

ENTRY(BootEntry)

SECTIONS
{
	.text 0x100000 :
	{
		code = .; _code = .; __code = .;
		*(.text)
		. = ALIGN(4096);
	}

	.data :
	{	
		ConstrStart = .; _ConstrStart = .; __ConstrStart = .;
		*(.ctor*)
		ConstrEnd = .; _ConstrEnd = .; __ConstrEnd = .;
		
		DestrStart = .; _DestrStart = .; __DestrStart = .;
		*(.dtor*)
		DestrEnd = .; _DestrEnd = .; __DestrEnd = .;
	
		data = .; _data = .; __data = .;
		*(.data)
		*(.rodata)
		. = ALIGN(4096);
	}

	.bss :
	{
		bss = .; _bss = .; __bss = .;
		*(.bss)
		. = ALIGN(4096);
	}

	end = .; _end = .; __end = .;
}

INPUT
(
	Entry.o
	AsmImp.o
	
	CppInit.o
	GUI.o
	Main.o
	GRUB.o
	Kernel.o
	Keyboard.o
	
	Heap.o
	Memory.o
	OrderedList.o
	Paging.o
	String.o
	
	CCWrite.o
	Video.o
)

OUTPUT(Kernel.bin)

Code: Select all

; * * * * * * * * * * * * * * * * * * * * *
; Entry.asm
; * * * * * * * * * * * * * * * * * * * * *
[BITS 32]

[GLOBAL BootEntry]
[GLOBAL Multiboot]

[EXTERN _Kernel]

ALIGN 4
Multiboot:
	MULTIBOOT_PAGE_ALIGN	equ 1<<0
	MULTIBOOT_MEMORY_INFO	equ 1<<1
	MULTIBOOT_AOUT_KLUDGE	equ 1<<16
	MULTIBOOT_HEADER_MAGIC	equ 0x1BADB002
	MULTIBOOT_HEADER_FLAGS	equ MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_AOUT_KLUDGE
	MULTIBOOT_CHECKSUM		equ	-(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
	EXTERN code, bss, end

	dd MULTIBOOT_HEADER_MAGIC
	dd MULTIBOOT_HEADER_FLAGS
	dd MULTIBOOT_CHECKSUM

	dd Multiboot
	dd code
	dd bss
	dd end
	dd BootEntry

;========================================
; InitStaticConstr
;   - Calls C++ static/global constructors.
; ========================================
[EXTERN ConstrStart]
[EXTERN ConstrEnd]

InitStaticConstr:
	mov ebx, ConstrStart		; Load the first constructor.
	jmp .Compare				; Jump to the compare label.
	
	.Body:						; This is the body, it calls the constructor and increments the 'pointer'.
		call [ebx]				; Call the constructor.
		add ebx, 4				; Move to the next one.
	
	.Compare:					; This checks if we've reached the end of the constructor 'list'.
		cmp ebx, ConstrEnd		; Check if the constructor inside ebx is the last constructor.
		jb .Body				; If it isn't, go back to Body.
		
	ret							; Return, we're done here.
	
;========================================
; InitStaticDestr
;   - Calls C++ static/global constructors.
; ========================================
[EXTERN DestrStart]
[EXTERN DestrEnd]

InitStaticDestr:
	mov ebx, DestrStart			; Load the first destructor.
	jmp .Compare				; Jump to the compare label.
	
	.Body:						; This is the body, it calls the destructor and increments the 'pointer'.
		call [ebx]				; Call the destructor.
		add ebx, 4				; Move to the next one.
	
	.Compare:					; This checks if we've reached the end of the destructor 'list'.
		cmp ebx, DestrEnd		; Check if the destructor inside ebx is the last destructor.
		jb .Body				; If it isn't, go back to Body.
		
	ret							; Return, we're done here.

;========================================
; BootEntry
;   - This is where it all begins. The BIOS passes the command to
;     this function.
; ========================================
[SECTION .text]					; We're in a text section.
BootEntry:
	mov esp, StackEnd			; Setup the stack pointer to the end of the stack.

	push eax					; Grab the multiboot magic number (last argument of KernelEntry).
	push ebx					; Grab the multiboot information (first argument of KernelEntry).

	cli							; No more interrupts.
	
	call InitStaticConstr		; Call C++ static/global constructors.
	call _Kernel				; Jump to the kernel entry.
	call InitStaticDestr		; Call C++ static/global destructors.

	jmp $						; Jump into an endless loop (to stop the CPU).

;========================================
; StackBegin and StackEnd
;   - The stack is initialized here and memory is reserved. The
;     stack grows downwards instead of upwards.
; ========================================	
[SECTION .bss]					; We're in a BSS section for memory initialization.
StackBegin:						; The beginning of the stack.
	resb 4096					; Reserve 4 kB of memory.
StackEnd:						; The end of the stack.

Code: Select all

;========================================
; InitStaticDestr
;   - Calls C++ static/global constructors.
; ========================================
[EXTERN DestrStart]
[EXTERN DestrEnd]

InitStaticDestr:
	mov ebx, DestrEnd - 4		; Load the last destructor.
	jmp .Compare				; Jump to the compare label.
	
	.Body:						; This is the body, it calls the destructor and decrements the 'pointer'.
		call [ebx]				; Call the destructor.
		sub ebx, 4				; Move to the previous one.
	
	.Compare:					; This checks if we've reached the beginning of the destructor 'list'.
		cmp ebx, DestrStart		; Check if the destructor inside ebx is the first destructor.
		jb .Body				; If it isn't, go back to Body.
		
	ret							; Return, we're done here.