src: make CleanupHandles() tear down handles/reqs

Previously, handles would not be closed when the current `Environment`
stopped, which is acceptable in a single-`Environment`-per-process
situation, but would otherwise create memory and file descriptor
leaks.

Also, introduce a generic way to close handles via the
`Environment::CloseHandle()` function, which automatically keeps
track of whether a close callback has been called yet or not.

Many thanks for Stephen Belanger for reviewing the original version of
this commit in the Ayo.js project.

Refs: https://github.com/ayojs/ayo/pull/85
PR-URL: https://github.com/nodejs/node/pull/19377
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 12 insertions, 8 deletions

diff --git a/src/env.cc b/src/env.cc
index aadb81092e..6526c680ac 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -209,9 +209,7 @@ void Environment::RegisterHandleCleanups() {
                                         void* arg) {
     handle->data = env;
 
-    uv_close(handle, [](uv_handle_t* handle) {
-      static_cast<Environment*>(handle->data)->FinishHandleCleanup(handle);
-    });
+    env->CloseHandle(handle, [](uv_handle_t* handle) {});
   };
 
   RegisterHandleCleanup(
@@ -233,13 +231,17 @@ void Environment::RegisterHandleCleanups() {
 }
 
 void Environment::CleanupHandles() {
-  for (HandleCleanup& hc : handle_cleanup_queue_) {
-    handle_cleanup_waiting_++;
+  for (ReqWrap<uv_req_t>* request : req_wrap_queue_)
+    request->Cancel();
+
+  for (HandleWrap* handle : handle_wrap_queue_)
+    handle->Close();
+
+  for (HandleCleanup& hc : handle_cleanup_queue_)
     hc.cb_(this, hc.handle_, hc.arg_);
-  }
   handle_cleanup_queue_.clear();
 
-  while (handle_cleanup_waiting_ != 0)
+  while (handle_cleanup_waiting_ != 0 || !handle_wrap_queue_.IsEmpty())
     uv_run(event_loop(), UV_RUN_ONCE);
 }
 
@@ -306,6 +308,8 @@ void Environment::PrintSyncTrace() const {
 }
 
 void Environment::RunCleanup() {
+  CleanupHandles();
+
   while (!cleanup_hooks_.empty()) {
     // Copy into a vector, since we can't sort an unordered_set in-place.
     std::vector<CleanupHookCallback> callbacks(
@@ -329,8 +333,8 @@ void Environment::RunCleanup() {
 
       cb.fn_(cb.arg_);
       cleanup_hooks_.erase(cb);
-      CleanupHandles();
     }
+    CleanupHandles();
   }
 }