strncmp.s

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# Kernel Library
# strncmp

.include "f_asm.inc"

.equ STR1,	DES
.equ STR2,	SRC

.text

.global _strncmp

_strncmp:
	ENTER
		pushl %esi
		pushl %edi
		
		movl LEN(%ebp), %ecx
		movl STR1(%ebp), %esi
		movl STR2(%ebp), %edi
		
		xorl %eax, %eax
		cmpl %esi, %edi
		jz done
		
		cld	
next:
		movb (%esi), %dl
		cmpsb
		jnz diff
		cmpb $0, %dl
		loopnz next
		jmp done		
diff:		
		sbbl %eax, %eax
		orb $1, %al
done:
		popl %edi
		popl %esi
				
	LEAVE
		ret