Fix: Only do function call once

Author: Bartel-C8

src/incoming_msg.cc

@@ -15,7 +15,8 @@ IncomingMsg::~IncomingMsg() {
 }
 
 Napi::Value IncomingMsg::IntoBuffer(const Napi::Env& env) {
-    if (!hasElectronMemoryCage(env)) {
+    static auto const noElectronMemoryCage = !hasElectronMemoryCage(env);
+    if (noElectronMemoryCage) {
         if (moved) {
             /* If ownership has been transferred, do not attempt to read the buffer
                again in any case. This should not happen of course. */
@@ -26,7 +27,7 @@ Napi::Value IncomingMsg::IntoBuffer(const Napi::Env& env) {
     auto data = reinterpret_cast<uint8_t*>(zmq_msg_data(*ref));
     auto length = zmq_msg_size(*ref);
 
-    if (!hasElectronMemoryCage(env)) {
+    if (noElectronMemoryCage) {
         static auto constexpr zero_copy_threshold = 1 << 7;
         if (length > zero_copy_threshold) {
             /* Reuse existing buffer for external storage. This avoids copying but