| //go:build windows |
| |
| /* |
| * Copyright 2023 gRPC authors. |
| * |
| * 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. |
| * |
| */ |
| |
| package internal |
| |
| import ( |
| "net" |
| "syscall" |
| "time" |
| |
| "golang.org/x/sys/windows" |
| ) |
| |
| // NetDialerWithTCPKeepalive returns a net.Dialer that enables TCP keepalives on |
| // the underlying connection with OS default values for keepalive parameters. |
| // |
| // TODO: Once https://github.com/golang/go/issues/62254 lands, and the |
| // appropriate Go version becomes less than our least supported Go version, we |
| // should look into using the new API to make things more straightforward. |
| func NetDialerWithTCPKeepalive() *net.Dialer { |
| return &net.Dialer{ |
| // Setting a negative value here prevents the Go stdlib from overriding |
| // the values of TCP keepalive time and interval. It also prevents the |
| // Go stdlib from enabling TCP keepalives by default. |
| KeepAlive: time.Duration(-1), |
| // This method is called after the underlying network socket is created, |
| // but before dialing the socket (or calling its connect() method). The |
| // combination of unconditionally enabling TCP keepalives here, and |
| // disabling the overriding of TCP keepalive parameters by setting the |
| // KeepAlive field to a negative value above, results in OS defaults for |
| // the TCP keealive interval and time parameters. |
| Control: func(_, _ string, c syscall.RawConn) error { |
| return c.Control(func(fd uintptr) { |
| windows.SetsockoptInt(windows.Handle(fd), windows.SOL_SOCKET, windows.SO_KEEPALIVE, 1) |
| }) |
| }, |
| } |
| } |