src: make IsolateData store ArrayBufferAllocator

This enables us to identify whether we are using an
allocator that we know more about than what the generic
`ArrayBuffer::Allocator` API provides, in particular
whether it is `malloc()`-compatible.

PR-URL: https://github.com/nodejs/node/pull/26207
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

4 files changed, 29 insertions, 16 deletions

diff --git a/src/api/environment.cc b/src/api/environment.cc
index 689f82bf24..7b6de8ba8d 100644
--- a/src/api/environment.cc
+++ b/src/api/environment.cc
@@ -124,11 +124,7 @@ IsolateData* CreateIsolateData(Isolate* isolate,
                                uv_loop_t* loop,
                                MultiIsolatePlatform* platform,
                                ArrayBufferAllocator* allocator) {
-  return new IsolateData(
-      isolate,
-      loop,
-      platform,
-      allocator != nullptr ? allocator->zero_fill_field() : nullptr);
+  return new IsolateData(isolate, loop, platform, allocator);
 }
 
 void FreeIsolateData(IsolateData* isolate_data) {
diff --git a/src/env-inl.h b/src/env-inl.h
index aca8176056..51c7e0d7b0 100644
--- a/src/env-inl.h
+++ b/src/env-inl.h
@@ -49,8 +49,16 @@ inline uv_loop_t* IsolateData::event_loop() const {
   return event_loop_;
 }
 
-inline uint32_t* IsolateData::zero_fill_field() const {
-  return zero_fill_field_;
+inline bool IsolateData::uses_node_allocator() const {
+  return uses_node_allocator_;
+}
+
+inline v8::ArrayBuffer::Allocator* IsolateData::allocator() const {
+  return allocator_;
+}
+
+inline ArrayBufferAllocator* IsolateData::node_allocator() const {
+  return node_allocator_;
 }
 
 inline MultiIsolatePlatform* IsolateData::platform() const {
diff --git a/src/env.cc b/src/env.cc
index 01aee46440..b7b6d745d8 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -74,11 +74,14 @@ void* const Environment::kNodeContextTagPtr = const_cast<void*>(
 IsolateData::IsolateData(Isolate* isolate,
                          uv_loop_t* event_loop,
                          MultiIsolatePlatform* platform,
-                         uint32_t* zero_fill_field) :
-    isolate_(isolate),
-    event_loop_(event_loop),
-    zero_fill_field_(zero_fill_field),
-    platform_(platform) {
+                         ArrayBufferAllocator* node_allocator)
+    : isolate_(isolate),
+      event_loop_(event_loop),
+      allocator_(isolate->GetArrayBufferAllocator()),
+      node_allocator_(node_allocator),
+      uses_node_allocator_(allocator_ == node_allocator_),
+      platform_(platform) {
+  CHECK_NOT_NULL(allocator_);
   if (platform_ != nullptr)
     platform_->RegisterIsolate(isolate_, event_loop);
 
diff --git a/src/env.h b/src/env.h
index 5f578dd54a..527a28f695 100644
--- a/src/env.h
+++ b/src/env.h
@@ -394,16 +394,20 @@ class Environment;
 
 class IsolateData {
  public:
-  IsolateData(v8::Isolate* isolate, uv_loop_t* event_loop,
+  IsolateData(v8::Isolate* isolate,
+              uv_loop_t* event_loop,
               MultiIsolatePlatform* platform = nullptr,
-              uint32_t* zero_fill_field = nullptr);
+              ArrayBufferAllocator* node_allocator = nullptr);
   ~IsolateData();
   inline uv_loop_t* event_loop() const;
-  inline uint32_t* zero_fill_field() const;
   inline MultiIsolatePlatform* platform() const;
   inline std::shared_ptr<PerIsolateOptions> options();
   inline void set_options(std::shared_ptr<PerIsolateOptions> options);
 
+  inline bool uses_node_allocator() const;
+  inline v8::ArrayBuffer::Allocator* allocator() const;
+  inline ArrayBufferAllocator* node_allocator() const;
+
 #define VP(PropertyName, StringValue) V(v8::Private, PropertyName)
 #define VY(PropertyName, StringValue) V(v8::Symbol, PropertyName)
 #define VS(PropertyName, StringValue) V(v8::String, PropertyName)
@@ -436,7 +440,9 @@ class IsolateData {
 
   v8::Isolate* const isolate_;
   uv_loop_t* const event_loop_;
-  uint32_t* const zero_fill_field_;
+  v8::ArrayBuffer::Allocator* const allocator_;
+  ArrayBufferAllocator* const node_allocator_;
+  const bool uses_node_allocator_;
   MultiIsolatePlatform* platform_;
   std::shared_ptr<PerIsolateOptions> options_;