tailscale/control/controlclient/hostinfo_windows.go

40 lines
962 B
Go

// 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 controlclient
import (
"os/exec"
"strings"
"sync/atomic"
"syscall"
)
func init() {
osVersion = osVersionWindows
}
var winVerCache atomic.Value // of string
func osVersionWindows() string {
if s, ok := winVerCache.Load().(string); ok {
return s
}
cmd := exec.Command("cmd", "/c", "ver")
cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
out, _ := cmd.Output() // "\nMicrosoft Windows [Version 10.0.19041.388]\n\n"
s := strings.TrimSpace(string(out))
s = strings.TrimPrefix(s, "Microsoft Windows [")
s = strings.TrimSuffix(s, "]")
// "Version 10.x.y.z", with "Version" localized. Keep only stuff after the space.
if sp := strings.Index(s, " "); sp != -1 {
s = s[sp+1:]
}
if s != "" {
winVerCache.Store(s)
}
return s // "10.0.19041.388", ideally
}