blob: 258dc63502775c9d813758df815dd591bcae7198 [file] [log] [blame]
// Copyright 2013 The Chromium Authors. All rights reserved.
// 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/logging.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