#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/mount.h>

int main(int argc, char **argv)
{
	int tree_fd;
	int ret;

	if (argc != 3) {
		fprintf(stderr, "usage: %s SOURCE MOUNTPOINT\n", argv[0]);
		return 2;
	}

	tree_fd = open_tree(AT_FDCWD, argv[1],
			    OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC | AT_SYMLINK_NOFOLLOW);
	if (tree_fd < 0) {
		fprintf(stderr, "open_tree(%s): %m\n", argv[1]);
		return 1;
	}

	ret = move_mount(tree_fd, "", AT_FDCWD, argv[2], MOVE_MOUNT_F_EMPTY_PATH);
	if (ret) {
		fprintf(stderr, "move_mount(%s): %m\n", argv[2]);
		return 1;
	}

	return 0;
}