stricmp.s

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# Kernel Library
# stricmp

.include "f_asm.inc"

.equ STR1,	DES
.equ STR2,	SRC

.text

.global _stricmp

_stricmp:
	ENTER
		pushl %esi
		movl %edi, %edx
		
		movl STR1(%ebp), %esi
		movl STR2(%ebp), %edi
		
		xorl %eax, %eax
		cmpl %esi, %edi
		jz done
	
next:
		movb (%esi), %cl
		cmpsb
		jz ignore
		lahf
		movb -1(%edi), %ch
		cmpb $0x41, %cl; jl diff
		cmpb $0x5a, %cl; jg comp0
		addb $0x20, %cl
comp0:	
		cmpb $0x41, %ch; jl diff
		cmpb $0x5a, %ch; jg comp1
		addb $0x20, %ch
comp1:
		cmpb %cl, %ch
		jnz diff
		xorb %ah, %ah
ignore:		
		cmpb $0, %cl
		jnz next
		jmp done				
		
diff:	
		xorl %ecx, %ecx	
		sahf		
		sbbl %ecx, %ecx
		orb $1, %cl
		movl %ecx, %eax
done:
		movl %edx, %edi
		popl %esi
				
	LEAVE
		ret