entry.s

用于汇编领域的,运用于OS的MAIN函数.基于硬件基础的源代码

.text
.code32

ret_from_exception:
	popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	iret

.global	divide_error
.align 4
divide_error:
	pushl	$0
	pushl	$do_divide_error
.align 4
error_code:
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx

	movl	40(%esp), %eax		# function address
	call	*%eax
	jmp	ret_from_exception


.extern do_dummy_interrupt_handler
.global dummy_interrupt_handler
.align 4
dummy_interrupt_handler:
	cli
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx
	cld
	call	do_dummy_interrupt_handler
	popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	sti
	iret

.extern schedule
.extern timer_handler
.global timer_isr
.align 4
timer_isr:
	cli
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx
	cld
	call	timer_handler
        call    schedule
	popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	sti
	iret


.extern kbd_handler
.global kbd_isr
.align 4
kbd_isr:
	cli
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx
	cld
	call	kbd_handler
	popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	sti
	iret

.extern floppy_handler
.global floppy_isr
.align 4
floppy_isr:
	cli
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx
	cld
	call	floppy_handler
	popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	sti
	iret

.extern display_regs2
.global ret_from_fork
.global system_call
.align 4
system_call:
	cli
	pushl	%fs
	pushl	%es
	pushl	%ds
	pushl	%eax
	pushl	%ebp
	pushl	%edi
	pushl	%esi
	pushl	%edx
	pushl	%ecx
	pushl	%ebx
	cld
	call    *(sys_call_table)(,%eax,4)	
ret_from_fork:
        call    display_regs2
        popl	%ebx
	popl	%ecx
	popl	%edx
	popl	%esi
	popl	%edi
	popl	%ebp
	popl	%eax
	popl	%ds
	popl	%es
	popl	%fs
	sti
	iret

.data
sys_call_table:
        .long sys_ni_syscall
	.long sys_exit
	.long sys_fork
	.long sys_read
	.long sys_write