网卡对象 绑定IP地址 然后向网卡对象写入数据 数据中将包含dst和src

tcpip/time_unsafe.go

@@ -0,0 +1,42 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.9
+
+package tcpip
+
+import (
+	_ "time"   // Used with go:linkname.
+	_ "unsafe" // Required for go:linkname.
+)
+
+// StdClock implements Clock with the time package.
+type StdClock struct{}
+
+var _ Clock = (*StdClock)(nil)
+
+//go:linkname now time.now
+func now() (sec int64, nsec int32, mono int64)
+
+// NowNanoseconds implements Clock.NowNanoseconds.
+func (*StdClock) NowNanoseconds() int64 {
+	sec, nsec, _ := now()
+	return sec*1e9 + int64(nsec)
+}
+
+// NowMonotonic implements Clock.NowMonotonic.
+func (*StdClock) NowMonotonic() int64 {
+	_, _, mono := now()
+	return mono
+}