1.4.5.2

EdgeNode/internal/utils/linkedlist/list.go

@@ -0,0 +1,111 @@
+// Copyright 2022 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package linkedlist
+
+type List[T any] struct {
+	head  *Item[T]
+	end   *Item[T]
+	count int
+}
+
+func NewList[T any]() *List[T] {
+	return &List[T]{}
+}
+
+func (this *List[T]) Head() *Item[T] {
+	return this.head
+}
+
+func (this *List[T]) End() *Item[T] {
+	return this.end
+}
+
+func (this *List[T]) Push(item *Item[T]) {
+	if item == nil {
+		return
+	}
+
+	// 如果已经在末尾了，则do nothing
+	if this.end == item {
+		return
+	}
+
+	if item.prev != nil || item.next != nil || this.head == item {
+		this.Remove(item)
+	}
+	this.add(item)
+}
+
+func (this *List[T]) Shift() *Item[T] {
+	if this.head != nil {
+		var old = this.head
+		this.Remove(this.head)
+		return old
+	}
+	return nil
+}
+
+func (this *List[T]) Remove(item *Item[T]) {
+	if item == nil {
+		return
+	}
+	if item.prev != nil {
+		item.prev.next = item.next
+	}
+	if item.next != nil {
+		item.next.prev = item.prev
+	}
+	if item == this.head {
+		this.head = item.next
+	}
+	if item == this.end {
+		this.end = item.prev
+	}
+
+	item.prev = nil
+	item.next = nil
+	this.count--
+}
+
+func (this *List[T]) Len() int {
+	return this.count
+}
+
+func (this *List[T]) Range(f func(item *Item[T]) (goNext bool)) {
+	for e := this.head; e != nil; e = e.next {
+		goNext := f(e)
+		if !goNext {
+			break
+		}
+	}
+}
+
+func (this *List[T]) RangeReverse(f func(item *Item[T]) (goNext bool)) {
+	for e := this.end; e != nil; e = e.prev {
+		goNext := f(e)
+		if !goNext {
+			break
+		}
+	}
+}
+
+func (this *List[T]) Reset() {
+	this.head = nil
+	this.end = nil
+}
+
+func (this *List[T]) add(item *Item[T]) {
+	if item == nil {
+		return
+	}
+	if this.end != nil {
+		this.end.next = item
+		item.prev = this.end
+		item.next = nil
+	}
+	this.end = item
+	if this.head == nil {
+		this.head = item
+	}
+	this.count++
+}