Archipelago

xqindex __xq_resize(struct xq *xq, struct xq *newxq)

{

	xqindex i, mask, mask_new, head, tail, val;

	xqindex nr = xq_count(xq);

	if (nr > newxq->size) {

		return Noneidx;

	}

	mask = xq->size -1;

	mask_new = newxq->size -1;

	head = __xq_peek_head_idx(xq, nr);

	tail = __xq_append_tail_idx(newxq, nr) + nr -1;

	for (i = 0; i < nr; i++) {

		val = XPTR(&xq->queue)[(head + i) & mask];

		XPTR(&newxq->queue)[(tail - i) & mask_new] = val;

	}

	return nr;

}

xqindex xq_resize(struct xq *xq, struct xq *newxq, unsigned long who)

{

	xqindex r = Noneidx;

	xlock_acquire(&xq->lock, who);

	xlock_acquire(&newxq->lock, who);

	r = __xq_resize(xq, newxq);

	xlock_release(&newxq->lock);

	xlock_release(&xq->lock);

	return r;

}