src: use RAII to manage the main isolate data

This patch encapsulates the main isolate management into a
NodeMainInstance class that manages the resources with RAII
and controls the Isolate::CreateParams (which is necessary
for deserializing snapshots with external references)

PR-URL: https://github.com/nodejs/node/pull/27220
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 14 insertions, 10 deletions

diff --git a/src/api/environment.cc b/src/api/environment.cc
index 70228b77d8..0543e0323d 100644
--- a/src/api/environment.cc
+++ b/src/api/environment.cc
@@ -169,11 +169,7 @@ void FreeArrayBufferAllocator(ArrayBufferAllocator* allocator) {
   delete allocator;
 }
 
-void SetIsolateCreateParams(Isolate::CreateParams* params,
-                            ArrayBufferAllocator* allocator) {
-  if (allocator != nullptr)
-    params->array_buffer_allocator = allocator;
-
+void SetIsolateCreateParamsForNode(Isolate::CreateParams* params) {
   const uint64_t total_memory = uv_get_total_memory();
   if (total_memory > 0) {
     // V8 defaults to 700MB or 1.4GB on 32 and 64 bit platforms respectively.
@@ -204,25 +200,33 @@ Isolate* NewIsolate(ArrayBufferAllocator* allocator, uv_loop_t* event_loop) {
   return NewIsolate(allocator, event_loop, GetMainThreadMultiIsolatePlatform());
 }
 
-Isolate* NewIsolate(ArrayBufferAllocator* allocator,
+// TODO(joyeecheung): we may want to expose this, but then we need to be
+// careful about what we override in the params.
+Isolate* NewIsolate(Isolate::CreateParams* params,
                     uv_loop_t* event_loop,
                     MultiIsolatePlatform* platform) {
-  Isolate::CreateParams params;
-  SetIsolateCreateParams(&params, allocator);
-
   Isolate* isolate = Isolate::Allocate();
   if (isolate == nullptr) return nullptr;
 
   // Register the isolate on the platform before the isolate gets initialized,
   // so that the isolate can access the platform during initialization.
   platform->RegisterIsolate(isolate, event_loop);
-  Isolate::Initialize(isolate, params);
 
+  SetIsolateCreateParamsForNode(params);
+  Isolate::Initialize(isolate, *params);
   SetIsolateUpForNode(isolate);
 
   return isolate;
 }
 
+Isolate* NewIsolate(ArrayBufferAllocator* allocator,
+                    uv_loop_t* event_loop,
+                    MultiIsolatePlatform* platform) {
+  Isolate::CreateParams params;
+  if (allocator != nullptr) params.array_buffer_allocator = allocator;
+  return NewIsolate(&params, event_loop, platform);
+}
+
 IsolateData* CreateIsolateData(Isolate* isolate,
                                uv_loop_t* loop,
                                MultiIsolatePlatform* platform,