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global int_syscall_handler
[extern syscall_exit]
[extern syscall_write]
[extern syscall_read]
[extern syscall_readdir]
[extern syscall_execve]
[extern syscall_open]
[extern syscall_close]
[extern syscall_fstat]
[extern syscall_isatty]
[extern syscall_lseek]
[extern syscall_sbrk]
[extern syscall_unhandled]
[bits 32]
int_syscall_handler:
cli
push ebx
push ecx
push edx
cmp eax, 60
je call_exit
cmp eax, 61
je call_write
cmp eax, 62
je call_read
cmp eax, 63
je call_readdir
cmp eax, 64
je call_execve
cmp eax, 65
je call_open
cmp eax, 66
je call_close
cmp eax, 67
je call_fstat
cmp eax, 68
je call_isatty
cmp eax, 69
je call_lseek
cmp eax, 70
je call_sbrk
push eax
jmp call_unhandled
done:
mov ebx,eax
mov al, 0x20 ;Port number AND command number to Acknowledge IRQ
out 0x20, al ;Acknowledge IRQ, so we keep getting interrupts
mov eax,ebx
done_blocking:
pop ebx
pop ecx
pop edx
mov ebx,eax
sti
iret ;Interrupt-Return
call_write:
call syscall_write
jmp done
call_open:
call syscall_open
jmp done
call_readdir:
call syscall_readdir
jmp done
call_close:
call syscall_close
jmp done
call_fstat:
call syscall_fstat
jmp done
call_isatty:
call syscall_isatty
jmp done
call_lseek:
call syscall_lseek
jmp done
call_sbrk:
call syscall_sbrk
jmp done
call_exit:
call syscall_exit
jmp done
call_unhandled:
call syscall_unhandled
jmp done ;this should never be called, since unhandled causes kernel panic
;;; THIS CALLS NEED REENABLE INTERRUPTS BEFORE calling workers
call_read:
mov al, 0x20 ;Port number AND command number to Acknowledge IRQ
out 0x20, al ;Acknowledge IRQ, so we keep getting interrupts
sti
call syscall_read
jmp done_blocking
call_execve:
mov al, 0x20 ;Port number AND command number to Acknowledge IRQ
out 0x20, al ;Acknowledge IRQ, so we keep getting interrupts
sti
call syscall_execve
jmp $ ; this should never return TODO: pop stack!?
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