.data

ReadBuffer:	.space		80
ReadPar:	.word		0, ReadBuffer, 80

PrintfPar:	.space		4

SaveR2:		.space		4
SaveR3:		.space		4
SaveR4:		.space		4
SaveR5:		.space		4

napis: .asciiz "Wprowadz 1 liczbe calkowita (moze byc ze znakiem) = "
.align 2

.text

.global		czytaj
czytaj:
	;*** save register contents
	sw		SaveR2,r2
	sw		SaveR3,r3
	sw		SaveR4,r4
	sw		SaveR5,r5

	addi r1, r0, napis
	sw		PrintfPar,r1
	addi		r14,r0,PrintfPar
	trap		5

	;*** call Trap-3 to read line
	addi		r14,r0,ReadPar
	trap		3

	;*** determine value
	addi		r2,r0,ReadBuffer
	addi		r1,r0,0
	addi		r4,r0,10	;Decimal system

Loop:		;*** reads digits to end of line
	lbu		r3,0(r2)
	seqi		r5,r3,10	;LF -> Exit
	bnez		r5,Finish
	subi		r3,r3,48	;´0´
	multu		r1,r1,r4	;Shift decimal
	add		r1,r1,r3
	addi		r2,r2,1 	;increment pointer
	j		Loop

Finish: 	;*** restore old register contents
	lw		r2,SaveR2
	lw		r3,SaveR3
	lw		r4,SaveR4
	lw		r5,SaveR5
	jr		r31		; Return