81 lines
1.8 KiB
Go
81 lines
1.8 KiB
Go
// Copyright 2023-2024 The NATS Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package stree
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// Node with 256 children
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// Order of struct fields for best memory alignment (as per govet/fieldalignment)
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type node256 struct {
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child [256]node
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meta
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}
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func newNode256(prefix []byte) *node256 {
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nn := &node256{}
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nn.setPrefix(prefix)
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return nn
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}
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func (n *node256) addChild(c byte, nn node) {
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n.child[c] = nn
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n.size++
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}
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func (n *node256) findChild(c byte) *node {
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if n.child[c] != nil {
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return &n.child[c]
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}
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return nil
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}
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func (n *node256) isFull() bool { return false }
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func (n *node256) grow() node { panic("grow can not be called on node256") }
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// Deletes a child from the node.
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func (n *node256) deleteChild(c byte) {
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if n.child[c] != nil {
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n.child[c] = nil
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n.size--
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}
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}
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// Shrink if needed and return new node, otherwise return nil.
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func (n *node256) shrink() node {
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if n.size > 48 {
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return nil
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}
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nn := newNode48(nil)
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for c, child := range n.child {
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if child != nil {
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nn.addChild(byte(c), n.child[c])
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}
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}
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return nn
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}
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// Iterate over all children calling func f.
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func (n *node256) iter(f func(node) bool) {
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for i := 0; i < 256; i++ {
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if n.child[i] != nil {
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if !f(n.child[i]) {
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return
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}
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}
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}
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}
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// Return our children as a slice.
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func (n *node256) children() []node {
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return n.child[:256]
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}
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