зеркало из https://github.com/mozilla/gecko-dev.git
119 строки
2.9 KiB
C++
119 строки
2.9 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#ifndef mozilla_mscom_AgileReference_h
|
|
#define mozilla_mscom_AgileReference_h
|
|
|
|
#include "mozilla/RefPtr.h"
|
|
|
|
#include <objidl.h>
|
|
|
|
namespace mozilla {
|
|
namespace mscom {
|
|
|
|
/**
|
|
* This class encapsulates an "agile reference." These are references that
|
|
* allow you to pass COM interfaces between apartments. When you have an
|
|
* interface that you would like to pass between apartments, you wrap that
|
|
* interface in an AgileReference and pass the agile reference instead. Then
|
|
* you unwrap the interface by calling AgileReference::Resolve.
|
|
*
|
|
* Sample usage:
|
|
*
|
|
* // In the multithreaded apartment, foo is an IFoo*
|
|
* auto myAgileRef = MakeUnique<AgileReference>(IID_IFoo, foo);
|
|
*
|
|
* // myAgileRef is passed to our main thread, which runs in a single-threaded
|
|
* // apartment:
|
|
*
|
|
* RefPtr<IFoo> foo;
|
|
* HRESULT hr = myAgileRef->Resolve(IID_IFoo, getter_AddRefs(foo));
|
|
* // Now foo may be called from the main thread
|
|
*/
|
|
class AgileReference final
|
|
{
|
|
public:
|
|
AgileReference();
|
|
|
|
template <typename InterfaceT>
|
|
explicit AgileReference(RefPtr<InterfaceT>& aObject)
|
|
: AgileReference(__uuidof(InterfaceT), aObject)
|
|
{
|
|
}
|
|
|
|
AgileReference(REFIID aIid, IUnknown* aObject);
|
|
AgileReference(AgileReference&& aOther);
|
|
|
|
~AgileReference();
|
|
|
|
explicit operator bool() const
|
|
{
|
|
return mAgileRef || mGitCookie;
|
|
}
|
|
|
|
template <typename T>
|
|
void Assign(const RefPtr<T>& aOther)
|
|
{
|
|
Assign(__uuidof(T), aOther);
|
|
}
|
|
|
|
template <typename T>
|
|
AgileReference& operator=(const RefPtr<T>& aOther)
|
|
{
|
|
Assign(aOther);
|
|
return *this;
|
|
}
|
|
|
|
HRESULT Resolve(REFIID aIid, void** aOutInterface) const;
|
|
|
|
AgileReference(const AgileReference& aOther) = delete;
|
|
AgileReference& operator=(const AgileReference& aOther) = delete;
|
|
|
|
AgileReference& operator=(AgileReference&& aOther);
|
|
|
|
AgileReference& operator=(decltype(nullptr))
|
|
{
|
|
Clear();
|
|
return *this;
|
|
}
|
|
|
|
void Clear();
|
|
|
|
private:
|
|
void Assign(REFIID aIid, IUnknown* aObject);
|
|
void AssignInternal(IUnknown* aObject);
|
|
static IGlobalInterfaceTable* ObtainGit();
|
|
|
|
private:
|
|
IID mIid;
|
|
RefPtr<IAgileReference> mAgileRef;
|
|
DWORD mGitCookie;
|
|
};
|
|
|
|
} // namespace mscom
|
|
} // namespace mozilla
|
|
|
|
template <typename T>
|
|
RefPtr<T>::RefPtr(const mozilla::mscom::AgileReference& aAgileRef)
|
|
: mRawPtr(nullptr)
|
|
{
|
|
(*this) = aAgileRef;
|
|
}
|
|
|
|
template <typename T>
|
|
RefPtr<T>&
|
|
RefPtr<T>::operator=(const mozilla::mscom::AgileReference& aAgileRef)
|
|
{
|
|
void* newRawPtr;
|
|
if (FAILED(aAgileRef.Resolve(__uuidof(T), &newRawPtr))) {
|
|
newRawPtr = nullptr;
|
|
}
|
|
assign_assuming_AddRef(static_cast<T*>(newRawPtr));
|
|
return *this;
|
|
}
|
|
|
|
#endif // mozilla_mscom_AgileReference_h
|