Move Linux client & common packages into a public repo.

wgengine/faketun.go

@@ -0,0 +1,55 @@
+// 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.
+
+package wgengine
+
+import (
+	"github.com/tailscale/wireguard-go/tun"
+	"io"
+	"os"
+)
+
+type fakeTun struct {
+	datachan  chan []byte
+	evchan    chan tun.Event
+	closechan chan struct{}
+}
+
+func NewFakeTun() tun.Device {
+	return &fakeTun{
+		datachan:  make(chan []byte),
+		evchan:    make(chan tun.Event),
+		closechan: make(chan struct{}),
+	}
+}
+
+func (t *fakeTun) File() *os.File {
+	panic("fakeTun.File() called, which makes no sense")
+}
+
+func (t *fakeTun) Close() error {
+	close(t.closechan)
+	close(t.datachan)
+	return nil
+}
+
+func (t *fakeTun) InsertRead(b []byte) {
+	t.datachan <- b
+}
+
+func (t *fakeTun) Read(out []byte, offset int) (int, error) {
+	select {
+	case <-t.closechan:
+		return 0, io.EOF
+	case b := <-t.datachan:
+		copy(out[offset:offset+len(b)], b)
+		return len(b), nil
+	}
+}
+
+func (t *fakeTun) Write(b []byte, n int) (int, error) { return len(b), nil }
+func (t *fakeTun) Flush() error                       { return nil }
+func (t *fakeTun) MTU() (int, error)                  { return 1500, nil }
+func (t *fakeTun) Name() (string, error)              { return "FakeTun", nil }
+func (t *fakeTun) Events() chan tun.Event             { return t.evchan }