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 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
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 * Please obtain a copy of the License at
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#include "mocks/std_safe.h"
#include "unit_test_utils.h"
#include "fibers/fibers.h"
#include <kern/locks_internal.h>

extern int ut_mocks_use_fibers;

static struct fibers_queue mcs_queue;

T_MOCK_F(lck_mcs_node_t,
lck_mcs_enqueue, (
	lck_mcs_id_t           * link,
	lck_mcs_mode_t          mode,
	void                   *lock,
	hw_spin_policy_t        pol), (link, mode, lock, pol))
{
	if (ut_mocks_use_fibers) {
		fibers_queue_push(&mcs_queue, fibers_current);
		if (fibers_queue_peek(&mcs_queue) != fibers_current) {
			fibers_choose_next(FIBER_WAIT);
		}
		return NULL;
	} else {
		return lck_mcs_enqueue(link, mode, lock, pol);
	}
}

T_MOCK_F(void,
lck_mcs_dequeue, (
	lck_mcs_node_t node,
	lck_mcs_id_t *link,
	lck_mcs_mode_t mode), (node, link, mode))
{
	if (ut_mocks_use_fibers) {
		fiber_t removed = fibers_queue_peek(&mcs_queue);
		FIBERS_ASSERT(removed == fibers_current, "lck_mcs_dequeue: expected that the thread dequeuing was the top of the mcs queue");
		fibers_queue_pop(&mcs_queue, fibers_queue_count(&mcs_queue) - 1);
		fiber_t awakened = fibers_queue_peek(&mcs_queue);
		if (awakened) {
			FIBERS_ASSERT(awakened->state == FIBER_WAIT, "lck_mcs_dequeue: new holder %d is not FIBER_WAIT", awakened->id);
			fibers_queue_push(&fibers_run_queue, awakened);
			fibers_may_yield_internal();
		}
	} else {
		return lck_mcs_dequeue(node, link, mode);
	}
}