From 73ad1f804b2fb89ebe6028b4f69d0ab99ecca29e Mon Sep 17 00:00:00 2001
From: Josh Bleecher Snyder <josharian@gmail.com>
Date: Fri, 30 Apr 2021 15:34:03 -0700
Subject: [PATCH] wgengine/wgcfg: use autogenerated Clone methods

Delete the manually written ones named Copy.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
---
 wgengine/userspace.go    |  2 +-
 wgengine/wgcfg/clone.go  | 61 ++++++++++++++++++++++++++++++++++++++++
 wgengine/wgcfg/config.go | 30 ++------------------
 3 files changed, 64 insertions(+), 29 deletions(-)
 create mode 100644 wgengine/wgcfg/clone.go

diff --git a/wgengine/userspace.go b/wgengine/userspace.go
index a3dd75375..d90cb8533 100644
--- a/wgengine/userspace.go
+++ b/wgengine/userspace.go
@@ -816,7 +816,7 @@ func (e *userspaceEngine) Reconfig(cfg *wgcfg.Config, routerCfg *router.Config,
 		}
 	}
 
-	e.lastCfgFull = cfg.Copy()
+	e.lastCfgFull = *cfg.Clone()
 
 	// Tell magicsock about the new (or initial) private key
 	// (which is needed by DERP) before wgdev gets it, as wgdev
diff --git a/wgengine/wgcfg/clone.go b/wgengine/wgcfg/clone.go
new file mode 100644
index 000000000..1b35a5d95
--- /dev/null
+++ b/wgengine/wgcfg/clone.go
@@ -0,0 +1,61 @@
+// Copyright (c) 2020 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 -type Config,Peer; DO NOT EDIT.
+
+package wgcfg
+
+import (
+	"inet.af/netaddr"
+	"tailscale.com/types/wgkey"
+)
+
+// 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 command:
+//   tailscale.com/cmd/cloner -type Config,Peer
+var _ConfigNeedsRegeneration = Config(struct {
+	Name       string
+	PrivateKey wgkey.Private
+	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 command:
+//   tailscale.com/cmd/cloner -type Config,Peer
+var _PeerNeedsRegeneration = Peer(struct {
+	PublicKey           wgkey.Key
+	AllowedIPs          []netaddr.IPPrefix
+	Endpoints           string
+	PersistentKeepalive uint16
+}{})
diff --git a/wgengine/wgcfg/config.go b/wgengine/wgcfg/config.go
index aa8850e5d..15b66cee4 100644
--- a/wgengine/wgcfg/config.go
+++ b/wgengine/wgcfg/config.go
@@ -10,6 +10,8 @@ import (
 	"tailscale.com/types/wgkey"
 )
 
+//go:generate go run tailscale.com/cmd/cloner -type=Config,Peer -output=clone.go
+
 // EndpointDiscoSuffix is appended to the hex representation of a peer's discovery key
 // and is then the sole wireguard endpoint for peers with a non-zero discovery key.
 // This form is then recognize by magicsock's CreateEndpoint.
@@ -33,34 +35,6 @@ type Peer struct {
 	PersistentKeepalive uint16
 }
 
-// Copy makes a deep copy of Config.
-// The result aliases no memory with the original.
-func (cfg Config) Copy() Config {
-	res := cfg
-	if res.Addresses != nil {
-		res.Addresses = append([]netaddr.IPPrefix{}, res.Addresses...)
-	}
-	if res.DNS != nil {
-		res.DNS = append([]netaddr.IP{}, res.DNS...)
-	}
-	peers := make([]Peer, 0, len(res.Peers))
-	for _, peer := range res.Peers {
-		peers = append(peers, peer.Copy())
-	}
-	res.Peers = peers
-	return res
-}
-
-// Copy makes a deep copy of Peer.
-// The result aliases no memory with the original.
-func (peer Peer) Copy() Peer {
-	res := peer
-	if res.AllowedIPs != nil {
-		res.AllowedIPs = append([]netaddr.IPPrefix{}, res.AllowedIPs...)
-	}
-	return res
-}
-
 // PeerWithKey returns the Peer with key k and reports whether it was found.
 func (config Config) PeerWithKey(k wgkey.Key) (Peer, bool) {
 	for _, p := range config.Peers {