cmd/cloner,util/codegen: refactor cloner internals to allow reuse

Also run go generate again for Copyright updates.

Signed-off-by: Maisem Ali <maisem@tailscale.com>

wgengine/wgcfg/wgcfg_clone.go

@@ -0,0 +1,60 @@
+// Copyright (c) 2022 Tailscale Inc & AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Code generated by tailscale.com/cmd/cloner; DO NOT EDIT.
+
+package wgcfg
+
+import (
+	"inet.af/netaddr"
+	"tailscale.com/types/key"
+)
+
+// Clone makes a deep copy of Config.
+// The result aliases no memory with the original.
+func (src *Config) Clone() *Config {
+	if src == nil {
+		return nil
+	}
+	dst := new(Config)
+	*dst = *src
+	dst.Addresses = append(src.Addresses[:0:0], src.Addresses...)
+	dst.DNS = append(src.DNS[:0:0], src.DNS...)
+	dst.Peers = make([]Peer, len(src.Peers))
+	for i := range dst.Peers {
+		dst.Peers[i] = *src.Peers[i].Clone()
+	}
+	return dst
+}
+
+// A compilation failure here means this code must be regenerated, with the command at the top of this file.
+var _ConfigCloneNeedsRegeneration = Config(struct {
+	Name       string
+	PrivateKey key.NodePrivate
+	Addresses  []netaddr.IPPrefix
+	MTU        uint16
+	DNS        []netaddr.IP
+	Peers      []Peer
+}{})
+
+// Clone makes a deep copy of Peer.
+// The result aliases no memory with the original.
+func (src *Peer) Clone() *Peer {
+	if src == nil {
+		return nil
+	}
+	dst := new(Peer)
+	*dst = *src
+	dst.AllowedIPs = append(src.AllowedIPs[:0:0], src.AllowedIPs...)
+	return dst
+}
+
+// A compilation failure here means this code must be regenerated, with the command at the top of this file.
+var _PeerCloneNeedsRegeneration = Peer(struct {
+	PublicKey           key.NodePublic
+	DiscoKey            key.DiscoPublic
+	AllowedIPs          []netaddr.IPPrefix
+	PersistentKeepalive uint16
+	WGEndpoint          key.NodePublic
+}{})