Mojo C++ Bindings: Extract AssociatedGroupController from MultiplexRouter

mojo/public/cpp/bindings/lib/interface_endpoint_client.h

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_ENDPOINT_CLIENT_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_ENDPOINT_CLIENT_H_
-
-#include <stdint.h>
-
-#include <map>
-#include <memory>
-
-#include "base/callback.h"
-#include "base/logging.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/weak_ptr.h"
-#include "base/single_thread_task_runner.h"
-#include "base/threading/thread_checker.h"
-#include "mojo/public/cpp/bindings/message.h"
-#include "mojo/public/cpp/bindings/message_filter.h"
-#include "mojo/public/cpp/bindings/scoped_interface_endpoint_handle.h"
-
-namespace mojo {
-
-class AssociatedGroup;
-
-namespace internal {
-
-class MultiplexRouter;
-class InterfaceEndpointController;
-
-// InterfaceEndpointClient handles message sending and receiving of an interface
-// endpoint, either the implementation side or the client side.
-// It should only be accessed and destructed on the creating thread.
-class InterfaceEndpointClient : public MessageReceiverWithResponder {
- public:
-  // |receiver| is okay to be null. If it is not null, it must outlive this
-  // object.
-  InterfaceEndpointClient(ScopedInterfaceEndpointHandle handle,
-                          MessageReceiverWithResponderStatus* receiver,
-                          std::unique_ptr<MessageFilter> payload_validator,
-                          bool expect_sync_requests,
-                          scoped_refptr<base::SingleThreadTaskRunner> runner);
-  ~InterfaceEndpointClient() override;
-
-  // Sets the error handler to receive notifications when an error is
-  // encountered.
-  void set_connection_error_handler(const base::Closure& error_handler) {
-    DCHECK(thread_checker_.CalledOnValidThread());
-    error_handler_ = error_handler;
-  }
-
-  // Returns true if an error was encountered.
-  bool encountered_error() const {
-    DCHECK(thread_checker_.CalledOnValidThread());
-    return encountered_error_;
-  }
-
-  // Returns true if this endpoint has any pending callbacks.
-  bool has_pending_responders() const {
-    DCHECK(thread_checker_.CalledOnValidThread());
-    return !async_responders_.empty() || !sync_responses_.empty();
-  }
-
-  MultiplexRouter* router() const { return handle_.router(); }
-  AssociatedGroup* associated_group();
-  uint32_t interface_id() const;
-
-  // After this call the object is in an invalid state and shouldn't be reused.
-  ScopedInterfaceEndpointHandle PassHandle();
-
-  // Raises an error on the underlying message pipe. It disconnects the pipe
-  // and notifies all interfaces running on this pipe.
-  void RaiseError();
-
-  // MessageReceiverWithResponder implementation:
-  bool Accept(Message* message) override;
-  bool AcceptWithResponder(Message* message,
-                           MessageReceiver* responder) override;
-
-  // The following methods are called by the router. They must be called
-  // outside of the router's lock.
-
-  // NOTE: |message| must have passed message header validation.
-  bool HandleIncomingMessage(Message* message);
-  void NotifyError();
-
- private:
-  // Maps from the id of a response to the MessageReceiver that handles the
-  // response.
-  using AsyncResponderMap =
-      std::map<uint64_t, std::unique_ptr<MessageReceiver>>;
-
-  struct SyncResponseInfo {
-   public:
-    explicit SyncResponseInfo(bool* in_response_received);
-    ~SyncResponseInfo();
-
-    std::unique_ptr<Message> response;
-
-    // Points to a stack-allocated variable.
-    bool* response_received;
-
-   private:
-    DISALLOW_COPY_AND_ASSIGN(SyncResponseInfo);
-  };
-
-  using SyncResponseMap = std::map<uint64_t, std::unique_ptr<SyncResponseInfo>>;
-
-  // Used as the sink for |payload_validator_| and forwards messages to
-  // HandleValidatedMessage().
-  class HandleIncomingMessageThunk : public MessageReceiver {
-   public:
-    explicit HandleIncomingMessageThunk(InterfaceEndpointClient* owner);
-    ~HandleIncomingMessageThunk() override;
-
-    // MessageReceiver implementation:
-    bool Accept(Message* message) override;
-
-   private:
-    InterfaceEndpointClient* const owner_;
-
-    DISALLOW_COPY_AND_ASSIGN(HandleIncomingMessageThunk);
-  };
-
-  bool HandleValidatedMessage(Message* message);
-
-  ScopedInterfaceEndpointHandle handle_;
-  std::unique_ptr<AssociatedGroup> associated_group_;
-  InterfaceEndpointController* controller_;
-
-  MessageReceiverWithResponderStatus* const incoming_receiver_;
-  std::unique_ptr<MessageFilter> payload_validator_;
-  HandleIncomingMessageThunk thunk_;
-
-  AsyncResponderMap async_responders_;
-  SyncResponseMap sync_responses_;
-
-  uint64_t next_request_id_;
-
-  base::Closure error_handler_;
-  bool encountered_error_;
-
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-
-  base::ThreadChecker thread_checker_;
-
-  base::WeakPtrFactory<InterfaceEndpointClient> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(InterfaceEndpointClient);
-};
-
-}  // namespace internal
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_ENDPOINT_CLIENT_H_