初版功能完成

internal/overlay/clientwg/muxtun_test.go

@@ -0,0 +1,96 @@
+package clientwg
+
+import (
+	"errors"
+	"os"
+	"testing"
+
+	"golang.zx2c4.com/wireguard/tun"
+)
+
+func TestMuxTunProxiesBaseSemanticsAndClosesOnce(t *testing.T) {
+	t.Parallel()
+	base := newFakeTUN()
+	mux := NewMuxTun(base)
+	if name, err := mux.Name(); err != nil || name != "RemLink" {
+		t.Fatalf("Name() = (%q, %v)", name, err)
+	}
+	if mtu, err := mux.MTU(); err != nil || mtu != 1280 {
+		t.Fatalf("MTU() = (%d, %v)", mtu, err)
+	}
+	if mux.BatchSize() != 1 {
+		t.Fatalf("BatchSize() = %d, want 1", mux.BatchSize())
+	}
+	if mux.Events() != base.events {
+		t.Fatal("Events() did not return the base channel")
+	}
+
+	buffer := make([]byte, 32)
+	sizes := make([]int, 1)
+	n, err := mux.Read([][]byte{buffer}, sizes, 4)
+	if err != nil || n != 1 || sizes[0] != 3 || string(buffer[4:7]) != "out" {
+		t.Fatalf("Read() = n=%d sizes=%v data=%q err=%v", n, sizes, buffer[4:7], err)
+	}
+	n, err = mux.Write([][]byte{[]byte("xxxxin")}, 4)
+	if err != nil || n != 1 || string(base.written) != "in" {
+		t.Fatalf("Write() = n=%d written=%q err=%v", n, base.written, err)
+	}
+
+	if err := mux.Close(); err != nil {
+		t.Fatalf("Close() error = %v", err)
+	}
+	if err := mux.Close(); err != nil {
+		t.Fatalf("second Close() error = %v", err)
+	}
+	if base.closeCalls != 1 {
+		t.Fatalf("base Close() calls = %d, want 1", base.closeCalls)
+	}
+}
+
+func TestMuxTunPreservesBaseErrors(t *testing.T) {
+	t.Parallel()
+	want := errors.New("read failed")
+	base := newFakeTUN()
+	base.readErr = want
+	_, err := NewMuxTun(base).Read([][]byte{make([]byte, 8)}, make([]int, 1), 0)
+	if !errors.Is(err, want) {
+		t.Fatalf("Read() error = %v, want %v", err, want)
+	}
+}
+
+type fakeTUN struct {
+	events     chan tun.Event
+	written    []byte
+	readErr    error
+	closeCalls int
+}
+
+func newFakeTUN() *fakeTUN {
+	return &fakeTUN{events: make(chan tun.Event, 1)}
+}
+
+func (f *fakeTUN) File() *os.File { return nil }
+
+func (f *fakeTUN) Read(bufs [][]byte, sizes []int, offset int) (int, error) {
+	if f.readErr != nil {
+		return 0, f.readErr
+	}
+	sizes[0] = copy(bufs[0][offset:], []byte("out"))
+	return 1, nil
+}
+
+func (f *fakeTUN) Write(bufs [][]byte, offset int) (int, error) {
+	f.written = append(f.written[:0], bufs[0][offset:]...)
+	return len(bufs), nil
+}
+
+func (f *fakeTUN) MTU() (int, error)     { return 1280, nil }
+func (f *fakeTUN) Name() (string, error) { return "RemLink", nil }
+func (f *fakeTUN) Events() <-chan tun.Event {
+	return f.events
+}
+func (f *fakeTUN) Close() error {
+	f.closeCalls++
+	return nil
+}
+func (f *fakeTUN) BatchSize() int { return 1 }