limit change to writePointer

Update to avoid changing behaviour for
_writePointer and limit change to writePointer
where objects were already being associated
with the buffer.

Signed-off-by: Michael Dawson <mdawson@devrus.com>

lib/ref.js

@@ -746,7 +746,7 @@ exports.writeObject = function writeObject (buf, offset, obj) {
 
 exports.writePointer = function writePointer (buf, offset, ptr) {
   debug('writing pointer to buffer', buf, offset, ptr);
-  exports._writePointer(buf, offset, ptr);
+  exports._writePointer(buf, offset, ptr, true);
   exports._attach(buf, ptr);
 };
 

src/binding.cc

@@ -355,15 +355,17 @@ void WritePointer(const CallbackInfo& args) {
   if (input.IsNull()) {
     *reinterpret_cast<char**>(ptr) = nullptr;
   } else {
-    // create a node-api reference and finalizer to ensure that
-    // the buffer whoes pointer is written can only be
-    // collected after the finalizers for the buffer
-    // to which the pointer was written have already run
-    Reference<Value>* ref = new Reference<Value>;
-    *ref = Persistent(args[2]);
-    args[0].As<Object>().AddFinalizer([](Env env, Reference<Value>* ref) {
-      delete ref;
-    }, ref);
+    if ((args.Length() == 4) && (args[3].As<Boolean>() == true)) {
+      // create a node-api reference and finalizer to ensure that
+      // the buffer whoes pointer is written can only be
+      // collected after the finalizers for the buffer
+      // to which the pointer was written have already run
+      Reference<Value>* ref = new Reference<Value>;
+      *ref = Persistent(args[2]);
+      args[0].As<Object>().AddFinalizer([](Env env, Reference<Value>* ref) {
+        delete ref;
+      }, ref);
+    }
 
     char* input_ptr = GetBufferData(input);
     *reinterpret_cast<char**>(ptr) = input_ptr;