1#define _BSD_SOURCE
 2#include <errno.h>
 3#include <stdlib.h>
 4
 5void *reallocarray(void *ptr, size_t m, size_t n)
 6{
 7	if (n && m > -1 / n) {
 8		errno = ENOMEM;
 9		return 0;
10	}
11
12	return realloc(ptr, m * n);
13}