实现WAF

internal/grids/list.go

@@ -0,0 +1,68 @@
+package grids
+
+type List struct {
+	head *Item
+	end  *Item
+}
+
+func NewList() *List {
+	return &List{}
+}
+
+func (this *List) Add(item *Item) {
+	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
+	}
+}
+
+func (this *List) Remove(item *Item) {
+	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
+}
+
+func (this *List) Len() int {
+	l := 0
+	for e := this.head; e != nil; e = e.Next {
+		l ++
+	}
+	return l
+}
+
+func (this *List) Range(f func(item *Item) (goNext bool)) {
+	for e := this.head; e != nil; e = e.Next {
+		goNext := f(e)
+		if !goNext {
+			break
+		}
+	}
+}
+
+func (this *List) Reset() {
+	this.head = nil
+	this.end = nil
+}