chromium/extensions/browser/extension_api_frame_id_map.h

// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef EXTENSIONS_BROWSER_EXTENSION_API_FRAME_ID_MAP_H_
#define EXTENSIONS_BROWSER_EXTENSION_API_FRAME_ID_MAP_H_

#include <map>
#include <memory>
#include <set>

#include "base/lazy_instance.h"
#include "base/unguessable_token.h"
#include "base/uuid.h"
#include "content/public/browser/document_user_data.h"
#include "content/public/browser/frame_type.h"
#include "content/public/browser/global_routing_id.h"
#include "extensions/common/api/extension_types.h"

namespace content {
class NavigationHandle;
class RenderFrameHost;
class WebContents;
}  // namespace content

namespace extensions {

// Extension frame IDs are exposed through the chrome.* APIs and have the
// following characteristics:
// - The top-level frame has ID 0.
// - Any child frame has a positive ID.
// - A non-existent frame has ID -1.
// - They are only guaranteed to be unique within a tab.
// - The ID does not change during the frame's lifetime and is not re-used after
//   the frame is removed. The frame may change its current RenderFrameHost over
//   time, so multiple RenderFrameHosts may map to the same extension frame ID.
//
// This class provides a mapping from a (render_process_id, frame_routing_id)
// pair to a FrameData struct, which includes the extension's frame id (as
// described above), the parent frame id, and the tab id (the latter can be
// invalid if it's not in a tab).
//
// Unless stated otherwise, the methods can only be called on the UI thread.
//
// The non-static methods of this class use an internal cache.
class ExtensionApiFrameIdMap { … };

}  // namespace extensions

#endif  // EXTENSIONS_BROWSER_EXTENSION_API_FRAME_ID_MAP_H_