struct result_buf {
	unsigned long array[24*1024*1024];
	int len;
};

struct result_buf rbuf;

int read(int fd, void *buf, unsigned long len);
void *malloc(unsigned long);
long strlen(char *);
int open(char *, int flags, long mode);
int printf(char *, ...);
void exit(int);
int strncmp(char *, char *, unsigned long);

void rabin_karp(char *p, int plen, char *t, int tlen)
{
	unsigned long d = 129;
	unsigned long h = 1, p_h = 0, t_h = 0;
	int i;
	for (i = 0; i < plen - 1; ++i)
		h = (h * d);

	for (i = 0; i < plen; ++i) {
		p_h = (d*p_h + p[i]);
		t_h = (d*t_h + t[i]);
	}


	for (i = 0; i <= tlen - plen; ++i) {

		if (p_h == t_h && strncmp(t + i, p, plen) == 0) {
			rbuf.array[rbuf.len] = i;
			++rbuf.len;
		}
		if (i < tlen - plen) {
			t_h = (d*(t_h - t[i]*h)) + t[i + plen];
		}
	}
}

void *read_file(int fd, int *len)
{
	int size = 1500 * 1024 * 1024;
	unsigned char *arr = malloc(size);
	int i;
	for (i = 0; ;) {
		int rd = read(fd, arr + i, size - i);
		if (rd < 0)
			exit(2);
		if (rd == 0)
			break;
		i += rd;
	}

	*len = i;
	return arr;
}

int main(int argc, char **argv)
{
	int i, slen;
	long sum = 0;
	int fd;
	char *buf;
	char *needle = argv[2];

	fd = open(argv[1], 0, 0);
	if (fd == -1)
		return 1;
	buf = read_file(fd, &slen);
	printf("len: %d\n", slen);

	rabin_karp(needle, strlen(needle), buf, slen);

	for (i = 0; i < rbuf.len; ++i)
		sum += rbuf.array[i];
	printf("%ld\n", sum);

	return 0;
}