the definitive tun offloads branch (#1704)

pprof_debug.go

@@ -0,0 +1,35 @@
+//go:build debug
+
+package nebula
+
+import (
+	"context"
+	"errors"
+	"log/slog"
+	"net/http"
+	_ "net/http/pprof" // registers pprof handlers on http.DefaultServeMux
+)
+
+// startPprofServer serves net/http/pprof on localhost:6060 for the life of
+// ctx. It is only compiled into debug builds (`-tags debug`, `make debug`),
+// so a debug build announces itself with the Info line below. Loopback only:
+// a wildcard bind would expose profiles (peer addresses, config-derived
+// state) to anything that can reach the host, the overlay included.
+func startPprofServer(ctx context.Context, l *slog.Logger) {
+	server := &http.Server{Addr: "localhost:6060", Handler: nil}
+	l.Info("Starting pprof debug server (debug build)", "addr", server.Addr)
+
+	go func() {
+		if err := server.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
+			l.Error("pprof debug server stopped", "error", err)
+		}
+	}()
+
+	// Shut down the server when the context is cancelled.
+	go func() {
+		<-ctx.Done()
+		if err := server.Shutdown(context.Background()); err != nil {
+			l.Debug("Error shutting down pprof debug server", "error", err)
+		}
+	}()
+}