session_storage_namespace_impl.h | Explore in Territory

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SERVICES_STORAGE_DOM_STORAGE_SESSION_STORAGE_NAMESPACE_IMPL_H_
#define COMPONENTS_SERVICES_STORAGE_DOM_STORAGE_SESSION_STORAGE_NAMESPACE_IMPL_H_

#include <map>
#include <memory>
#include <vector>

#include "base/containers/flat_set.h"
#include "base/functional/callback.h"
#include "base/gtest_prod_util.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "components/services/storage/dom_storage/session_storage_area_impl.h"
#include "components/services/storage/dom_storage/session_storage_data_map.h"
#include "components/services/storage/dom_storage/session_storage_metadata.h"
#include "mojo/public/cpp/bindings/pending_receiver.h"
#include "third_party/blink/public/common/storage_key/storage_key.h"
#include "third_party/blink/public/mojom/dom_storage/session_storage_namespace.mojom.h"

namespace storage {

class AsyncDomStorageDatabase;

// Implements the Blink SessionStorageNamespace interface. Stores data maps per
// StorageKey, which are accessible using the StorageArea interface with the
// |OpenArea| call. Supports cloning (shallow cloning with copy-on-write
// behavior) from another SessionStorageNamespaceImpl.
//
// This class is populated & bound in the following patterns:
// 1. The namespace is new or being populated from data on disk, and
//    |PopulateFromMetadata| is called. Afterwards |Bind| can be called.
// 2. The namespace is being created as a clone from a |Clone| call on another
//    SessionStorageNamespaceImpl. PopulateFromMetadata is called with the
//    data from the other namespace, and then |Bind| can be called afterwards.
// 3. The namespace is being created as a clone, but the |Clone| call from the
//    source namespace hasn't been called yet.
//    |set_pending_population_from_namespace| is called first, after which
//    |Bind| can be called. The actually binding doesn't happen until
//    |PopulateAsClone| is finally called with the source namespace data.
// Note: The reason for cases 2 and 3 is because there are two ways the Session
// Storage system knows about clones. First, it gets the |Clone| call on the
// source namespace, coming from the renderer doing the navigation, and in the
// correct order with any session storage modifications from that source
// renderer. Second, the RenderViewHostImpl of the navigated-to-frame will
// create the cloned namespace and expect to manage it's lifetime that way, and
// this can happen before the first case, as they are on different task runners.
class SessionStorageNamespaceImpl final
    : public blink::mojom::SessionStorageNamespace { … };

}  // namespace storage

#endif  // COMPONENTS_SERVICES_STORAGE_DOM_STORAGE_SESSION_STORAGE_NAMESPACE_IMPL_H_
chromium/components/services/storage/dom_storage/session_storage_namespace_impl.h
