usr/klibc/strcasecmp.c

/*
 * strcasecmp.c
 */

#include <string.h>
#include <ctype.h>

int strcasecmp(const char *s1, const char *s2)
{
	const unsigned char *c1 = (const unsigned char *)s1;
	const unsigned char *c2 = (const unsigned char *)s2;
	unsigned char ch;
	int d = 0;

	while (1) {
		/* toupper() expects an unsigned char (implicitly cast to int)
		   as input, and returns an int, which is exactly what we want. */
		d = toupper(ch = *c1++) - toupper(*c2++);
		if (d || !ch)
			break;
	}

	return d;
}