#include <stddef.h>
#include "include/string.h"

int memcmp(const void *lhs, const void *rhs, size_t n) {
	const unsigned char *l = lhs;
	const unsigned char *r = rhs;
	while(n != 0 && *l == *r) {
		n--;
		l++;
		r++;
	}
	return (n == 0) ? 0 : *l - *r;
}

void *memcpy(void *restrict dst, const void *restrict src, size_t n) {
	char *d = dst;
	const char *s = src;
	while(n--) {
		*d++ = *s++;
	}
	return dst;
}

void *memmove(void *dst, const void *src, size_t n) {
	char *d = dst;
	const char *s = src;
	if(s < d) {
		d += n;
		s += n;
		while(n--) {
			*--d = *--s;
		}
	} else {
		while(n--) {
			*d++ = *s++;
		}
	}
	return dst;
}

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

char *strcpy(char *restrict dst, const char *restrict src) {
	while((*dst = *src) != '\0') {
		dst++;
		src++;
	}
	return dst;
}

char *strncpy(char *restrict dst, const char *restrict src, size_t n) {
	while((*dst = *src) != '\0' && n != 0) {
		dst++;
		src++;
		n--;
	}
	memset(dst, 0, n);
	return dst;
}