gecko-dev/dom/storage/SessionStorageObserver.h

64 lines
1.8 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_dom_SessionStorageObserver_h
#define mozilla_dom_SessionStorageObserver_h
#include "nsISupportsImpl.h"
namespace mozilla::dom {
class SessionStorageObserverChild;
/**
* Effectively just a refcounted life-cycle management wrapper around
* SessionStorageObserverChild which exists to receive chrome observer
* notifications from the main process.
*
* ## Lifecycle ##
* - Created by SessionStorageManager::SessionStorageManager. Placed in the
* gSessionStorageObserver variable for subsequent SessionStorageManager's via
* SessionStorageObserver::Get lookup.
* - The SessionStorageObserverChild directly handles "Observe" messages,
* shunting them directly to StorageObserver::Notify which distributes them to
* individual observer sinks.
* - Destroyed when refcount goes to zero due to all owning
* SessionStorageManager being destroyed.
*/
class SessionStorageObserver final {
friend class SessionStorageManager;
SessionStorageObserverChild* mActor;
public:
static SessionStorageObserver* Get();
NS_INLINE_DECL_REFCOUNTING(SessionStorageObserver)
void AssertIsOnOwningThread() const {
NS_ASSERT_OWNINGTHREAD(SessionStorageObserver);
}
void SetActor(SessionStorageObserverChild* aActor);
void ClearActor() {
AssertIsOnOwningThread();
MOZ_ASSERT(mActor);
mActor = nullptr;
}
private:
// Only created by SessionStorageManager.
SessionStorageObserver();
~SessionStorageObserver();
};
} // namespace mozilla::dom
#endif // mozilla_dom_SessionStorageObserver_h