#include <string.h>

void *memcpy(void *restrict s1, const void *restrict s2, size_t n) {
	const unsigned char *restrict c2 = s2;
	unsigned char *restrict c1 = s1;

	while (n--) {
		*c1++ = *c2++;
	}
	return s1;
}

int memcmp(const void *s1, const void *s2, size_t n) {
	const unsigned char *u1 = s1;
	const unsigned char *u2 = s2;

    for (; n--; u1++, u2++) {
		if (*u1 != *u2) return *u1 - *u2;
    }

    return 0;
}

void *memset(void *s, int c, size_t n) {
	unsigned char *restrict buf = s;
	while (n--) {
		*buf++ = c;
	}
	return s;
}

int strcmp(const char *s1, const char *s2) {
	while (*s1 != 0 && *s2 != 0) {
		if (*s1 != *s2) break;
	}

	if(*s1 > *s2) return 1;
	if(*s1 < *s2) return -1;
	return 0;
}

size_t strlen(const char *s) {
	size_t i = 0;
	while (s[i]) {
		i++;
	}
	return i;
}

// __STDC_WANT_LIB_EXT1__
size_t strnlen_s(const char *s, size_t maxsize) {
	size_t i = 0;
	while (s[i] && i < maxsize) {
		i++;
	}
	return i;
}