src: allow generic C++ callables in SetImmediate()

Modify the native `SetImmediate()` functions to take generic C++
callables as arguments. This makes passing arguments to the callback
easier, and in particular, it allows passing `std::unique_ptr`s
directly, which in turn makes sure that the data they point to is
deleted if the `Environment` is torn down before the callback can run.

PR-URL: https://github.com/nodejs/node/pull/28704
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 31 insertions, 35 deletions

diff --git a/src/env.cc b/src/env.cc
index f0ac855e3d8..ca5e11ac558 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -339,7 +339,7 @@ Environment::Environment(IsolateData* isolate_data,
       [](void* arg) {
         Environment* env = static_cast<Environment*>(arg);
         if (!env->destroy_async_id_list()->empty())
-          AsyncWrap::DestroyAsyncIdsCallback(env, nullptr);
+          AsyncWrap::DestroyAsyncIdsCallback(env);
       },
       this);
 
@@ -642,42 +642,38 @@ void Environment::AtExit(void (*cb)(void* arg), void* arg) {
 void Environment::RunAndClearNativeImmediates() {
   TraceEventScope trace_scope(TRACING_CATEGORY_NODE1(environment),
                               "RunAndClearNativeImmediates", this);
-  size_t count = native_immediate_callbacks_.size();
-  if (count > 0) {
-    size_t ref_count = 0;
-    std::vector<NativeImmediateCallback> list;
-    native_immediate_callbacks_.swap(list);
-    auto drain_list = [&]() {
-      TryCatchScope try_catch(this);
-      for (auto it = list.begin(); it != list.end(); ++it) {
-        DebugSealHandleScope seal_handle_scope(isolate());
-        it->cb_(this, it->data_);
-        if (it->refed_)
-          ref_count++;
-        if (UNLIKELY(try_catch.HasCaught())) {
-          if (!try_catch.HasTerminated())
-            errors::TriggerUncaughtException(isolate(), try_catch);
-
-          // We are done with the current callback. Increase the counter so that
-          // the steps below make everything *after* the current item part of
-          // the new list.
-          it++;
-
-          // Bail out, remove the already executed callbacks from list
-          // and set up a new TryCatch for the other pending callbacks.
-          std::move_backward(it, list.end(), list.begin() + (list.end() - it));
-          list.resize(list.end() - it);
-          return true;
-        }
+  size_t ref_count = 0;
+  size_t count = 0;
+  std::unique_ptr<NativeImmediateCallback> head;
+  head.swap(native_immediate_callbacks_head_);
+  native_immediate_callbacks_tail_ = nullptr;
+
+  auto drain_list = [&]() {
+    TryCatchScope try_catch(this);
+    for (; head; head = head->get_next()) {
+      DebugSealHandleScope seal_handle_scope(isolate());
+      count++;
+      if (head->is_refed())
+        ref_count++;
+
+      head->Call(this);
+      if (UNLIKELY(try_catch.HasCaught())) {
+        if (!try_catch.HasTerminated())
+          errors::TriggerUncaughtException(isolate(), try_catch);
+
+        // We are done with the current callback. Move one iteration along,
+        // as if we had completed successfully.
+        head = head->get_next();
+        return true;
       }
-      return false;
-    };
-    while (drain_list()) {}
+    }
+    return false;
+  };
+  while (head && drain_list()) {}
 
-    DCHECK_GE(immediate_info()->count(), count);
-    immediate_info()->count_dec(count);
-    immediate_info()->ref_count_dec(ref_count);
-  }
+  DCHECK_GE(immediate_info()->count(), count);
+  immediate_info()->count_dec(count);
+  immediate_info()->ref_count_dec(ref_count);
 }