1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "gin/wrappable.h" 6 7 #include "base/logging.h" 8 #include "gin/object_template_builder.h" 9 #include "gin/per_isolate_data.h" 10 11 namespace gin { 12 13 WrappableBase::WrappableBase() { 14 } 15 16 WrappableBase::~WrappableBase() { 17 wrapper_.Reset(); 18 } 19 20 ObjectTemplateBuilder WrappableBase::GetObjectTemplateBuilder( 21 v8::Isolate* isolate) { 22 return ObjectTemplateBuilder(isolate); 23 } 24 25 void WrappableBase::WeakCallback( 26 const v8::WeakCallbackData<v8::Object, WrappableBase>& data) { 27 WrappableBase* wrappable = data.GetParameter(); 28 wrappable->wrapper_.Reset(); 29 delete wrappable; 30 } 31 32 v8::Handle<v8::Object> WrappableBase::GetWrapperImpl(v8::Isolate* isolate, 33 WrapperInfo* info) { 34 if (!wrapper_.IsEmpty()) { 35 return v8::Local<v8::Object>::New(isolate, wrapper_); 36 } 37 38 PerIsolateData* data = PerIsolateData::From(isolate); 39 v8::Local<v8::ObjectTemplate> templ = data->GetObjectTemplate(info); 40 if (templ.IsEmpty()) { 41 templ = GetObjectTemplateBuilder(isolate).Build(); 42 CHECK(!templ.IsEmpty()); 43 data->SetObjectTemplate(info, templ); 44 } 45 CHECK_EQ(kNumberOfInternalFields, templ->InternalFieldCount()); 46 v8::Handle<v8::Object> wrapper = templ->NewInstance(); 47 // |wrapper| may be empty in some extreme cases, e.g., when 48 // Object.prototype.constructor is overwritten. 49 if (wrapper.IsEmpty()) { 50 // The current wrappable object will be no longer managed by V8. Delete this 51 // now. 52 delete this; 53 return wrapper; 54 } 55 wrapper->SetAlignedPointerInInternalField(kWrapperInfoIndex, info); 56 wrapper->SetAlignedPointerInInternalField(kEncodedValueIndex, this); 57 wrapper_.Reset(isolate, wrapper); 58 wrapper_.SetWeak(this, WeakCallback); 59 return wrapper; 60 } 61 62 namespace internal { 63 64 void* FromV8Impl(v8::Isolate* isolate, v8::Handle<v8::Value> val, 65 WrapperInfo* wrapper_info) { 66 if (!val->IsObject()) 67 return NULL; 68 v8::Handle<v8::Object> obj = v8::Handle<v8::Object>::Cast(val); 69 WrapperInfo* info = WrapperInfo::From(obj); 70 71 // If this fails, the object is not managed by Gin. It is either a normal JS 72 // object that's not wrapping any external C++ object, or it is wrapping some 73 // C++ object, but that object isn't managed by Gin (maybe Blink). 74 if (!info) 75 return NULL; 76 77 // If this fails, the object is managed by Gin, but it's not wrapping an 78 // instance of the C++ class associated with wrapper_info. 79 if (info != wrapper_info) 80 return NULL; 81 82 return obj->GetAlignedPointerFromInternalField(kEncodedValueIndex); 83 } 84 85 } // namespace internal 86 87 } // namespace gin 88
