Implement the strcmp/strncmp function in C

Implement the strcmp/strncmp function in C

int stringcmp(char* s1,char* s2)
{
int stringlen=0;
while(*(s1+stringlen)!='\0' && *(s2+stringlen)!='\0')
if(*(s1+stringlen)!=*(s2+stringlen))
return *(s1+stringlen) - *(s2+stringlen);
else
stringlen++;

if(*(s1+stringlen)!='\0' || *(s2+stringlen)!='\0')return *(s1+stringlen) - *(s2+stringlen);

return 0;
}

Regards,
HCV