[#1] mclock: Refactor: split code between files

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

scheduling/queue.go

@@ -0,0 +1,100 @@
+package scheduling
+
+type queueItem interface {
+	ts() float64
+	setIndex(idx int)
+}
+
+type queue struct {
+	items []queueItem
+}
+
+// Len implements heap.Interface.
+func (q *queue) Len() int {
+	return len(q.items)
+}
+
+// Less implements heap.Interface.
+func (q *queue) Less(i int, j int) bool {
+	return q.items[i].ts() < q.items[j].ts()
+}
+
+// Pop implements heap.Interface.
+func (q *queue) Pop() any {
+	n := len(q.items)
+	item := q.items[n-1]
+	q.items[n-1] = nil
+	q.items = q.items[0 : n-1]
+	item.setIndex(invalidIndex)
+	return item
+}
+
+// Push implements heap.Interface.
+func (q *queue) Push(x any) {
+	it := x.(queueItem)
+	it.setIndex(q.Len())
+	q.items = append(q.items, it)
+}
+
+// Swap implements heap.Interface.
+func (q *queue) Swap(i int, j int) {
+	q.items[i], q.items[j] = q.items[j], q.items[i]
+	q.items[i].setIndex(i)
+	q.items[j].setIndex(j)
+}
+
+var _ queueItem = &reservationMQueueItem{}
+
+type reservationMQueueItem struct {
+	r *request
+}
+
+func (i *reservationMQueueItem) ts() float64 {
+	return i.r.reservation
+}
+
+func (i *reservationMQueueItem) setIndex(idx int) {
+	i.r.reservationIdx = idx
+}
+
+var _ queueItem = &limitMQueueItem{}
+
+type limitMQueueItem struct {
+	r *request
+}
+
+func (i *limitMQueueItem) ts() float64 {
+	return i.r.limit
+}
+
+func (i *limitMQueueItem) setIndex(idx int) {
+	i.r.limitIdx = idx
+}
+
+var _ queueItem = &sharesMQueueItem{}
+
+type sharesMQueueItem struct {
+	r *request
+}
+
+func (i *sharesMQueueItem) ts() float64 {
+	return i.r.shares
+}
+
+func (i *sharesMQueueItem) setIndex(idx int) {
+	i.r.sharesIdx = idx
+}
+
+var _ queueItem = &readyMQueueItem{}
+
+type readyMQueueItem struct {
+	r *request
+}
+
+func (i *readyMQueueItem) ts() float64 {
+	return i.r.shares
+}
+
+func (i *readyMQueueItem) setIndex(idx int) {
+	i.r.readyIdx = idx
+}