#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>

#include "random.h"

#define RAND_BUF_SIZE	1024
#define RND_DEV		"/dev/urandom"

unsigned int get_random(void)
{
	static int rndbuf[RAND_BUF_SIZE];
	static int index = RAND_BUF_SIZE;
	int fd, error, i = 0, ret;

	if (index < RAND_BUF_SIZE)
		return rndbuf[index++];

	fd = open(RND_DEV, O_RDONLY);
	if (fd < 0) {
		error = errno;
		fprintf(stderr, "Error opening file %s: %s\n",
			RND_DEV, strerror(error));
		return -1;
	}

	do {
		ret = read(fd, rndbuf + i,
			  RAND_BUF_SIZE * (sizeof(rndbuf[0]) - i));
		
		if (ret <= 0) {
			error = errno;
			fprintf(stderr, "Error reading file %s: %s\n",
				RND_DEV, strerror(error));
			goto out;
		}

		i += ret;
	} while (i < RAND_BUF_SIZE * sizeof(rndbuf[0]));
	index = 0;
 out:
	return get_random();
	close(fd);
}