Subversion Repositories Kolibri OS

; diamond, 2006

sys_debug_services:

	cmp	eax, 9

	ja	@f

	jmp	dword [sys_debug_services_table+eax*4]

@@:	ret

sys_debug_services_table:

	dd	debug_set_event_data

	dd	debug_getcontext

	dd	debug_setcontext

	dd	debug_detach

	dd	debug_suspend

	dd	debug_resume

	dd	debug_read_process_memory

	dd	debug_write_process_memory

	dd	debug_terminate

	dd	debug_set_drx

debug_set_event_data:

; in: ebx = pointer

; destroys eax

        mov     eax, [current_slot]

        mov     [eax+APPDATA.dbg_event_mem], ebx

	ret

get_debuggee_slot:

; in: ebx=PID

; out: CF=1 if error

;      CF=0 and eax=slot*0x20 if ok

; out: interrupts disabled

	cli

	mov	eax, ebx

	call	pid_to_slot

	test	eax, eax

	jz	.ret_bad

	shl	eax, 5

	push	ebx

        mov     ebx, [CURRENT_TASK]

        cmp     [SLOT_BASE+eax*8+APPDATA.debugger_slot], ebx

	pop	ebx

	jnz	.ret_bad

;	clc	; automatically

	ret

.ret_bad:

	stc

	ret

debug_detach:

; in: ebx=pid

; destroys eax,ebx

	call	get_debuggee_slot

	jc	.ret

        and     dword [eax*8+SLOT_BASE+APPDATA.debugger_slot], 0

	call	do_resume

.ret:

	sti

	ret

debug_terminate:

; in: ebx=pid

	call	get_debuggee_slot

	jc	debug_detach.ret

	mov	ebx, eax

	shr	ebx, 5

	push	2

	pop	eax

	jmp	sys_system

debug_suspend:

; in: ebx=pid

; destroys eax,ebx

	call	get_debuggee_slot

	jc	.ret

        mov     bl, [CURRENT_TASK+eax+TASKDATA.state] ; process state

	test	bl, bl

	jz	.1

	cmp	bl, 5

	jnz	.ret

	mov	bl, 2

.2:     mov     [CURRENT_TASK+eax+TASKDATA.state], bl

.ret:

	sti

	ret

.1:

	inc	ebx

	jmp	.2

do_resume:

        mov     bl, [CURRENT_TASK+eax+TASKDATA.state]

	cmp	bl, 1

	jz	.1

	cmp	bl, 2

	jnz	.ret

	mov	bl, 5

.2:     mov     [CURRENT_TASK+eax+TASKDATA.state], bl

.ret:	ret

.1:	dec	ebx

	jmp	.2

debug_resume:

; in: ebx=pid

; destroys eax,ebx

	call	get_debuggee_slot

	jc	.ret

	call	do_resume

.ret:	sti

	ret

debug_getcontext:

; in:

; ebx=pid

; ecx=sizeof(CONTEXT)

; edx->CONTEXT

; destroys eax,ecx,edx,esi,edi

	cmp	ecx, 28h

	jnz	.ret

    ;    add     edx, std_application_base_address

	push	ebx

	mov	ebx, edx

	call	check_region

	pop	ebx

	dec	eax

	jnz	.ret

	call	get_debuggee_slot

	jc	.ret

	imul	eax, tss_step/32

	add	eax, tss_data

	mov	edi, edx

        cmp     [eax+TSS._cs], app_code

	jnz	.ring0

        lea     esi, [eax+TSS._eip]

	shr	ecx, 2

	rep	movsd

	jmp	.ret

.ring0:

; note that following code assumes that all interrupt/exception handlers

; saves ring-3 context by pushad in this order

        mov     esi, [eax+TSS._esp0]

; top of ring0 stack: ring3 stack ptr (ss+esp), iret data (cs+eip+eflags), pushad

        sub     esi, 8+12+20h

        lodsd                     ;edi

	mov	[edi+24h], eax

        lodsd                     ;esi

	mov	[edi+20h], eax

        lodsd                     ; ebp

	mov	[edi+1Ch], eax

        lodsd                     ;esp

        lodsd                     ;ebx

	mov	[edi+14h], eax

        lodsd                     ;edx

	mov	[edi+10h], eax

        lodsd                     ;ecx

	mov	[edi+0Ch], eax

        lodsd                     ;eax

	mov	[edi+8], eax

;;;        add     esi, 8         ;ds es

        lodsd                     ;eip

	mov	[edi], eax

        lodsd                     ;cs

        lodsd                     ;eflags

	mov	[edi+4], eax

        lodsd                     ;esp

	mov	[edi+18h], eax

.ret:

	sti

	ret

debug_setcontext:

; in:

; ebx=pid

; ecx=sizeof(CONTEXT)

; edx->CONTEXT

; destroys eax,ecx,edx,esi,edi

	cmp	ecx, 28h

	jnz	.ret

    ;    add     edx, std_application_base_address

	push	ebx

	mov	ebx, edx

	call	check_region

	pop	ebx

	dec	eax

	jnz	.ret

	call	get_debuggee_slot

	jc	.stiret

	imul	eax, tss_step/32

	add	eax, tss_data

	mov	esi, edx

        cmp     [eax+TSS._cs], app_code

	jnz	.ring0

        lea     edi, [eax+TSS._eip]

	shr	ecx, 2

	rep	movsd

	jmp	.stiret

.ring0:

        mov     edi, [eax+TSS._esp0]

        sub     edi, 8+12+20h

        mov     eax, [esi+24h]    ;edi

	stosd

        mov     eax, [esi+20h]    ;esi

	stosd

        mov     eax, [esi+1Ch]    ;ebp

	stosd

        scasd

        mov     eax, [esi+14h]    ;ebx

	stosd

        mov     eax, [esi+10h]    ;edx

	stosd

        mov     eax, [esi+0Ch]    ;ecx

	stosd

        mov     eax, [esi+8]      ;eax

	stosd

;;;        add     edi, 8         ;ds es

        mov     eax, [esi]        ;eip

	stosd

	scasd

        mov     eax, [esi+4]      ;eflags

	stosd

        mov     eax, [esi+18h]    ;esp

	stosd

.stiret:

	sti

.ret:

	ret

debug_set_drx:

	call	get_debuggee_slot

	jc	.errret

	mov	ebp, eax

        lea     eax, [eax*8+SLOT_BASE+APPDATA.dbg_regs]

; [eax]=dr0, [eax+4]=dr1, [eax+8]=dr2, [eax+C]=dr3

; [eax+10]=dr7

    ;    add     edx, std_application_base_address

	jc	.errret

	cmp	cl, 3

	ja	.errret

	mov	ebx, dr7

	shr	ebx, cl

	shr	ebx, cl

	test	ebx, 2		; bit 1+2*index = G0..G3, global break enable

	jnz	.errret2

	test	ch, ch

	jns	.new

; clear breakpoint

	movzx	ecx, cl

	add	ecx, ecx

	and	dword [eax+ecx*2], 0	; clear DR

	btr	dword [eax+10h], ecx	; clear L bit

	test	byte [eax+10h], 55h

	jnz	.okret

	imul	eax, ebp, tss_step/32

        and     byte [eax + tss_data + TSS._trap], not 1

.okret:

	and	dword [esp+36], 0

	sti

	ret

.errret:

	sti

	mov	dword [esp+36], 1

	ret

.errret2:

	sti

	mov	dword [esp+36], 2

	ret

.new:

; add new breakpoint

; cl=index; ch=flags; edx=address

	test	ch, 0xF0

	jnz	.errret

	mov	bl, ch

	and	bl, 3

	cmp	bl, 2

	jz	.errret

	mov	bl, ch

	shr	bl, 2

	cmp	bl, 2

	jz	.errret

	test	dl, bl

	jnz	.errret

	or	byte [eax+10h+1], 3	; set GE and LE flags

	movzx	ebx, ch

	movzx	ecx, cl

	add	ecx, ecx

	bts	dword [eax+10h], ecx	; set L flag

	add	ecx, ecx

	mov	[eax+ecx], edx		; set DR

	shl	ebx, cl

	mov	edx, 0xF

	shl	edx, cl

	not	edx

	and	[eax+10h+2], dx

	or	[eax+10h+2], bx		; set R/W and LEN fields

	imul	eax, ebp, tss_step/32

        or      byte [eax + tss_data + TSS._trap], 1

	jmp	.okret

debug_read_process_memory:

; in:

; ebx=pid

; ecx=length

; esi->buffer in debugger

; edx=address in debuggee

; out: [esp+36]=sizeof(read)

; destroys all

    ;    add     esi, std_application_base_address

	push	ebx

	mov	ebx, esi

	call	check_region

	pop	ebx

	dec	eax

	jnz	.err

	call	get_debuggee_slot

	jc	.err

	shr	eax, 5

	mov	ebx, esi

	call	read_process_memory

	sti

	mov	dword [esp+36], eax

	ret

.err:

	or	dword [esp+36], -1

	ret

debug_write_process_memory:

; in:

; ebx=pid

; ecx=length

; esi->buffer in debugger

; edx=address in debuggee

; out: [esp+36]=sizeof(write)

; destroys all

    ;    add     esi, std_application_base_address

	push	ebx

	mov	ebx, esi

	call	check_region

	pop	ebx

	dec	eax

	jnz	debug_read_process_memory.err

	call	get_debuggee_slot

	jc	debug_read_process_memory.err

	shr	eax, 5

	mov	ebx, esi

	call	write_process_memory

	sti

	mov	[esp+36], eax

	ret

debugger_notify:

; in: eax=debugger slot

;     ecx=size of debug message

;     [esp+4]..[esp+4+ecx]=message

; interrupts must be disabled!

; destroys all general registers

; interrupts remain disabled

	xchg	ebp, eax

	mov	edi, [timer_ticks]

	add	edi, 500	; 5 sec timeout

.1:

	mov	eax, ebp

	shl	eax, 8

        mov     edx, [SLOT_BASE+eax+APPDATA.dbg_event_mem]

	test	edx, edx

	jz	.ret

; read buffer header

	push	ecx

	push	eax

	push	eax

	mov	eax, ebp

	mov	ebx, esp

	mov	ecx, 8

	call	read_process_memory

	cmp	eax, ecx

	jz	@f

	add	esp, 12

	jmp	.ret

@@:

	cmp	dword [ebx], 0

	jg	@f

.2:

	pop	ecx

	pop	ecx

	pop	ecx

        cmp     dword [CURRENT_TASK], 1

	jnz	.notos

	cmp	[timer_ticks], edi

	jae	.ret

.notos:

	sti

	call	change_task

	cli

	jmp	.1

@@:

	mov	ecx, [ebx+8]

	add	ecx, [ebx+4]

	cmp	ecx, [ebx]

	ja	.2

; advance buffer position

	push	ecx

	mov	ecx, 4

	sub	ebx, ecx

	mov	eax, ebp

	add	edx, ecx

	call	write_process_memory

	pop	eax

; write message

	mov	eax, ebp

	add	edx, ecx

	add	edx, [ebx+8]

	add	ebx, 20

	pop	ecx

	pop	ecx

	pop	ecx

	call	write_process_memory

; new debug event

	mov	eax, ebp

	shl	eax, 8

        or      byte [SLOT_BASE+eax+APPDATA.event_mask+1], 1      ; set flag 100h

.ret:

	ret

debug_exc:

; int 1 = #DB

	save_ring3_context

	cld

        mov     ax, app_data ;os_data

	mov	ds, ax

	mov	es, ax

	mov	eax, dr6

	test	ax, ax

	jns	@f

; this is exception from task switch

; set DRx registers for task and continue

        mov     eax, [CURRENT_TASK]

	shl	eax, 8

        add     eax, SLOT_BASE+APPDATA.dbg_regs

	mov	ecx, [eax+0]

	mov	dr0, ecx

	mov	ecx, [eax+4]

	mov	dr1, ecx

	mov	ecx, [eax+8]

	mov	dr2, ecx

	mov	ecx, [eax+0Ch]

	mov	dr3, ecx

	xor	ecx, ecx

	mov	dr6, ecx

	mov	ecx, [eax+10h]

	mov	dr7, ecx

	restore_ring3_context

	iretd

@@:

	push	eax

	xor	eax, eax

	mov	dr6, eax

; test if debugging

	cli

        mov     eax, [current_slot]

        mov     eax, [eax+APPDATA.debugger_slot]

	test	eax, eax

	jnz	.debug

	sti

; not debuggee => say error and terminate

        add     esp, 0x20+4

	mov	[error_interrupt], 1

	call	show_error_parameters

        mov     edx, [TASK_BASE]

	mov	byte [edx+TASKDATA.state], 4

	jmp	change_task

.debug:

; we are debugged process, notify debugger and suspend ourself

; eax=debugger PID

	pop	edx

	mov	ebx, dr7

	mov	cl, not 1

.l1:

	test	bl, 1

	jnz	@f

	and	dl, cl

@@:

	shr	ebx, 2

	add	cl, cl

	inc	ecx

	cmp	cl, not 10h

	jnz	.l1

	push	edx	; DR6 image

        mov     ecx, [TASK_BASE]

	push	dword [ecx+TASKDATA.pid]	; PID

	push	12

	pop	ecx

	push	3	; 3 = debug exception

	call	debugger_notify

	pop	ecx

	pop	ecx

	pop	ecx

        mov     edx, [TASK_BASE]

	mov	byte [edx+TASKDATA.state], 1	; suspended

	call	change_task

	restore_ring3_context

	iretd