src: close HandleWraps instead of deleting them in OnGCCollect()

When all strong `BaseObjectPtr`s to a `HandleWrap` are gone, we
should not delete the `HandleWrap` outright, but instead close
it and then delete it only once the libuv close callback has been
called.

Based on the valgrind output from the issue below, this has a
good chance of fixing it.

Fixes: https://github.com/nodejs/node/issues/39036

PR-URL: https://github.com/nodejs/node/pull/39441
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/src/handle_wrap.cc b/src/handle_wrap.cc
index d2bd67a5e40..caad0e05546 100644
--- a/src/handle_wrap.cc
+++ b/src/handle_wrap.cc
@@ -85,7 +85,16 @@ void HandleWrap::Close(Local<Value> close_callback) {
 
 
 void HandleWrap::OnGCCollect() {
-  Close();
+  // When all references to a HandleWrap are lost and the object is supposed to
+  // be destroyed, we first call Close() to clean up the underlying libuv
+  // handle. The OnClose callback then acquires and destroys another reference
+  // to that object, and when that reference is lost, we perform the default
+  // action (i.e. destroying `this`).
+  if (state_ != kClosed) {
+    Close();
+  } else {
+    BaseObject::OnGCCollect();
+  }
 }