global switch_to
extern ctask
extern tss

switch_to:
  push ebp
  mov ebp, esp
  mov eax, [ebp+8]
  mov [ctask], eax
  mov esi, [ebp+12]
  mov ecx, 13
.loop:
  lodsd
  push eax
  dec ecx
  jz .end
  jmp .loop
.end:
  mov ax, 0x23
  mov ds, ax
  mov es, ax
  mov fs, ax
  mov gs, ax
  popa
  iret

; uint32_t ss;
; uint32_t esp;
; uint32_t eflags;
; uint32_t cs;
; uint32_t eip;
; uint32_t eax;
; uint32_t ecx;
; uint32_t edx;
; uint32_t ebx;
; uint32_t esp_garbage;
; uint32_t ebp;
; uint32_t esi;
; uint32_t edi;

; switch_to:
  ; push ebp
  ; mov ebp, esp
  ; cli
  ; mov ax, 0x23
  ; mov ds, ax
  ; mov es, ax
  ; mov fs, ax
  ; mov gs, ax
  ; mov eax, esp
  ; ; save ESP in the TSS
  ; mov [tss+4], eax
  ; push dword 0x23
  ; push dword 0x00180000
  ; pushf
  ; push dword 0x1B
  ; push dword 0x00100000
  ; iret
  ; pop ebp
  ; ret