/*
* Copyright (C) 2014 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef V8GarbageCollected_h
#define V8GarbageCollected_h
#include <v8.h>
namespace WebCore {
template<typename T>
class V8GarbageCollected {
WTF_MAKE_NONCOPYABLE(V8GarbageCollected);
public:
static T* Cast(v8::Handle<v8::Value> value)
{
ASSERT(value->IsExternal());
T* result = static_cast<T*>(value.As<v8::External>()->Value());
RELEASE_ASSERT(result->m_handle == value);
return result;
}
protected:
V8GarbageCollected(v8::Isolate* isolate)
: m_isolate(isolate)
, m_handle(isolate, v8::External::New(isolate, static_cast<T*>(this)))
{
}
v8::Handle<v8::External> releaseToV8GarbageCollector()
{
ASSERT(!m_handle.isWeak()); // Call this exactly once.
v8::Handle<v8::External> result = m_handle.newLocal(m_isolate);
m_handle.setWeak(static_cast<T*>(this), &weakCallback);
return result;
}
~V8GarbageCollected()
{
ASSERT(m_handle.isEmpty());
}
v8::Isolate* isolate() { return m_isolate; }
private:
static void weakCallback(const v8::WeakCallbackData<v8::External, T>& data)
{
T* self = data.GetParameter();
self->m_handle.clear();
delete self;
}
v8::Isolate* m_isolate;
ScopedPersistent<v8::External> m_handle;
};
} // namespace WebCore
#endif // V8GarbageCollected_h