EtherGuard-VPN/device/tun.go
Josh Bleecher Snyder c9e4a859ae device: remove starting waitgroups
In each case, the starting waitgroup did nothing but ensure
that the goroutine has launched.

Nothing downstream depends on the order in which goroutines launch,
and if the Go runtime scheduler is so broken that goroutines
don't get launched reasonably promptly, we have much deeper problems.

Given all that, simplify the code.

Passed a race-enabled stress test 25,000 times without failure.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-01-07 14:49:44 +01:00

56 lines
1.2 KiB
Go

/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2020 WireGuard LLC. All Rights Reserved.
*/
package device
import (
"sync/atomic"
"golang.zx2c4.com/wireguard/tun"
)
const DefaultMTU = 1420
func (device *Device) RoutineTUNEventReader() {
setUp := false
logDebug := device.log.Debug
logInfo := device.log.Info
logError := device.log.Error
logDebug.Println("Routine: event worker - started")
for event := range device.tun.device.Events() {
if event&tun.EventMTUUpdate != 0 {
mtu, err := device.tun.device.MTU()
old := atomic.LoadInt32(&device.tun.mtu)
if err != nil {
logError.Println("Failed to load updated MTU of device:", err)
} else if int(old) != mtu {
if mtu+MessageTransportSize > MaxMessageSize {
logInfo.Println("MTU updated:", mtu, "(too large)")
} else {
logInfo.Println("MTU updated:", mtu)
}
atomic.StoreInt32(&device.tun.mtu, int32(mtu))
}
}
if event&tun.EventUp != 0 && !setUp {
logInfo.Println("Interface set up")
setUp = true
device.Up()
}
if event&tun.EventDown != 0 && setUp {
logInfo.Println("Interface set down")
setUp = false
device.Down()
}
}
logDebug.Println("Routine: event worker - stopped")
device.state.stopping.Done()
}