use sync.WaitGroup

Less handrolling, more idiomatic and easier to extend if need be.

Author: klemensn

cmd/yggdrasil/main.go

@@ -235,6 +235,7 @@ func main() {
 		}
 		if n.admin != nil {
 			n.admin.SetupAdminHandlers()
+			n.admin.Created.Add(1)
 		}
 	}
 
@@ -284,9 +285,10 @@ func main() {
 	// Change user if requested
 	if *chuserto != "" {
 		// Wait for other goroutines to finish potentially privileged tasks before dropping privileges.
-		doWait := n.admin != nil
-		// control socket:  UNIX requires filesystem permissions, TCP may use a low privileged port.
-		for ; doWait; doWait = !n.admin.Created {}
+		if n.admin != nil {
+			// control socket:  UNIX requires filesystem permissions, TCP may use a low privileged port.
+			n.admin.Created.Wait()
+		}
 
 		err = chuser(*chuserto)
 		if err != nil {

src/admin/admin.go

@@ -8,8 +8,8 @@ import (
 	"net/url"
 	"os"
 	"sort"
-
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/core"
@@ -26,7 +26,7 @@ type AdminSocket struct {
 	config   struct {
 		listenaddr ListenAddress
 	}
-	Created  bool
+	Created  sync.WaitGroup
 }
 
 type AdminSocketRequest struct {
@@ -275,7 +275,7 @@ func (a *AdminSocket) listen() {
 		a.log.Errorf("Admin socket failed to listen: %v", err)
 		os.Exit(1)
 	}
-	a.Created = true
+	a.Created.Done()
 	a.log.Infof("%s admin socket listening on %s",
 		strings.ToUpper(a.listener.Addr().Network()),
 		a.listener.Addr().String())