cmd/tailscale/cli: add RunWithContext

Fixes #12778

Change-Id: If9f8b299cef0cb68f93b344845b5c6a5b7554d2c
Signed-off-by: DeedleFake <deedlefake@users.noreply.github.com>

cmd/tailscale/cli/cli.go

@@ -93,8 +93,8 @@ var localClient = local.Client{
 	Socket: paths.DefaultTailscaledSocket(),
 }
 
-// Run runs the CLI. The args do not include the binary name.
-func Run(args []string) (err error) {
+// RunWithContext runs the CLI. The args do not include the binary name.
+func RunWithContext(ctx context.Context, args []string) (err error) {
 	if runtime.GOOS == "linux" && os.Getenv("GOKRAZY_FIRST_START") == "1" && distro.Get() == distro.Gokrazy && os.Getppid() == 1 && len(args) == 0 {
 		// We're running on gokrazy and the user did not specify 'up'.
 		// Don't run the tailscale CLI and spam logs with usage; just exit.
@@ -164,7 +164,7 @@ func Run(args []string) (err error) {
 		return
 	}
 
-	err = rootCmd.Run(context.Background())
+	err = rootCmd.Run(ctx)
 	if local.IsAccessDeniedError(err) && os.Getuid() != 0 && runtime.GOOS != "windows" {
 		return fmt.Errorf("%v\n\nUse 'sudo tailscale %s'.\nTo not require root, use 'sudo tailscale set --operator=$USER' once.", err, strings.Join(args, " "))
 	}
@@ -174,6 +174,11 @@ func Run(args []string) (err error) {
 	return err
 }
 
+// Run is equivalent to calling [RunWithContext] with the background context.
+func Run(args []string) (err error) {
+	return RunWithContext(context.Background(), args)
+}
+
 type onceFlagValue struct {
 	flag.Value
 	set bool