| // Copyright 2013 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "gin/wrappable.h" |
| |
| #include "base/check_op.h" |
| #include "gin/object_template_builder.h" |
| #include "gin/per_isolate_data.h" |
| |
| namespace gin { |
| |
| WrappableBase::WrappableBase() = default; |
| |
| WrappableBase::~WrappableBase() { |
| wrapper_.Reset(); |
| } |
| |
| ObjectTemplateBuilder WrappableBase::GetObjectTemplateBuilder( |
| v8::Isolate* isolate) { |
| return ObjectTemplateBuilder(isolate, GetTypeName()); |
| } |
| |
| const char* WrappableBase::GetTypeName() { |
| return nullptr; |
| } |
| |
| void WrappableBase::FirstWeakCallback( |
| const v8::WeakCallbackInfo<WrappableBase>& data) { |
| WrappableBase* wrappable = data.GetParameter(); |
| wrappable->dead_ = true; |
| wrappable->wrapper_.Reset(); |
| data.SetSecondPassCallback(SecondWeakCallback); |
| } |
| |
| void WrappableBase::SecondWeakCallback( |
| const v8::WeakCallbackInfo<WrappableBase>& data) { |
| WrappableBase* wrappable = data.GetParameter(); |
| delete wrappable; |
| } |
| |
| v8::MaybeLocal<v8::Object> WrappableBase::GetWrapperImpl(v8::Isolate* isolate, |
| WrapperInfo* info) { |
| if (!wrapper_.IsEmpty()) { |
| return v8::MaybeLocal<v8::Object>( |
| v8::Local<v8::Object>::New(isolate, wrapper_)); |
| } |
| |
| if (dead_) |
| return v8::MaybeLocal<v8::Object>(); |
| |
| PerIsolateData* data = PerIsolateData::From(isolate); |
| v8::Local<v8::ObjectTemplate> templ = data->GetObjectTemplate(info); |
| if (templ.IsEmpty()) { |
| templ = GetObjectTemplateBuilder(isolate).Build(); |
| CHECK(!templ.IsEmpty()); |
| data->SetObjectTemplate(info, templ); |
| } |
| CHECK_EQ(kNumberOfInternalFields, templ->InternalFieldCount()); |
| v8::Local<v8::Object> wrapper; |
| // |wrapper| may be empty in some extreme cases, e.g., when |
| // Object.prototype.constructor is overwritten. |
| if (!templ->NewInstance(isolate->GetCurrentContext()).ToLocal(&wrapper)) { |
| // The current wrappable object will be no longer managed by V8. Delete this |
| // now. |
| delete this; |
| return v8::MaybeLocal<v8::Object>(wrapper); |
| } |
| |
| int indices[] = {kWrapperInfoIndex, kEncodedValueIndex}; |
| void* values[] = {info, this}; |
| wrapper->SetAlignedPointerInInternalFields(2, indices, values); |
| wrapper_.Reset(isolate, wrapper); |
| wrapper_.SetWeak(this, FirstWeakCallback, v8::WeakCallbackType::kParameter); |
| return v8::MaybeLocal<v8::Object>(wrapper); |
| } |
| |
| namespace internal { |
| |
| void* FromV8Impl(v8::Isolate* isolate, v8::Local<v8::Value> val, |
| WrapperInfo* wrapper_info) { |
| if (!val->IsObject()) |
| return NULL; |
| v8::Local<v8::Object> obj = v8::Local<v8::Object>::Cast(val); |
| WrapperInfo* info = WrapperInfo::From(obj); |
| |
| // If this fails, the object is not managed by Gin. It is either a normal JS |
| // object that's not wrapping any external C++ object, or it is wrapping some |
| // C++ object, but that object isn't managed by Gin (maybe Blink). |
| if (!info) |
| return NULL; |
| |
| // If this fails, the object is managed by Gin, but it's not wrapping an |
| // instance of the C++ class associated with wrapper_info. |
| if (info != wrapper_info) |
| return NULL; |
| |
| return obj->GetAlignedPointerFromInternalField(kEncodedValueIndex); |
| } |
| |
| } // namespace internal |
| |
| } // namespace gin |