Restructure public side of network service.

mojo/services/public/cpp/network/udp_socket_wrapper.h

-// Copyright 2014 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_SERVICES_PUBLIC_CPP_NETWORK_UDP_SOCKET_WRAPPER_H_
-#define MOJO_SERVICES_PUBLIC_CPP_NETWORK_UDP_SOCKET_WRAPPER_H_
-
-#include <queue>
-
-#include "mojo/services/public/interfaces/network/udp_socket.mojom.h"
-
-namespace mojo {
-
-// This class is a wrapper around the UDPSocket interface. It provides local
-// cache for received datagrams as well as for (excessive) send requests:
-// - You call ReceiveFrom() to retrieve one datagram. If there is already cached
-//   data, the operation completes synchronously.
-// - You don't need to worry about the max-pending-send-requests restriction
-//   imposed by the service side. If you make many SendTo() calls in a short
-//   period of time, it caches excessive requests and sends them later.
-class UDPSocketWrapper : public UDPSocketClient {
- public:
-  typedef Callback<void(NetworkErrorPtr, NetAddressPtr, Array<uint8_t>)>
-      ReceiveCallback;
-  typedef Callback<void(NetworkErrorPtr)> ErrorCallback;
-
-  explicit UDPSocketWrapper(UDPSocketPtr socket);
-
-  // |receive_queue_slots| determines the size (in datagrams) of the local
-  // receive queue, which caches incoming datagrams.
-  // |requested_max_pending_sends| is used to call
-  // NegotiateMaxPendingSendRequests() on |socket|.
-  // The two numbers should be greater than 0. If you would like to use default
-  // values, please use the other constructor.
-  UDPSocketWrapper(UDPSocketPtr socket,
-                   uint32_t receive_queue_slots,
-                   uint32_t requested_max_pending_sends);
-
-  ~UDPSocketWrapper() override;
-
-  void AllowAddressReuse(const ErrorCallback& callback);
-
-  void Bind(NetAddressPtr addr,
-            const Callback<void(NetworkErrorPtr, NetAddressPtr)>& callback);
-
-  void SetSendBufferSize(uint32_t size, const ErrorCallback& callback);
-
-  void SetReceiveBufferSize(uint32_t size, const ErrorCallback& callback);
-
-  // If there are already incoming datagrams cached locally, this method runs
-  // |callback| before it returns, and the return value is set to true.
-  // Otherwise, the return value is set to false and the callback will be run
-  // asynchronously.
-  bool ReceiveFrom(const ReceiveCallback& callback);
-
-  // This method is aware of the max pending send requests allowed by the
-  // service, and caches send requests locally if necessary.
-  void SendTo(NetAddressPtr dest_addr,
-              Array<uint8_t> data,
-              const ErrorCallback& callback);
-
- private:
-  class NegotiateCallbackHandler : public Callback<void(uint32_t)>::Runnable {
-   public:
-    explicit NegotiateCallbackHandler(UDPSocketWrapper* delegate);
-    ~NegotiateCallbackHandler() override;
-
-    // Callback<void(uint32_t)>::Runnable implementation:
-    void Run(uint32_t actual_size) const override;
-
-   private:
-    // Because this callback is passed to a method of |socket_|, and |socket_|
-    // is owned by |delegate_|, it should be safe to assume that |delegate_| is
-    // valid if/when Run() is called.
-    UDPSocketWrapper* delegate_;
-  };
-
-  class SendCallbackHandler : public ErrorCallback::Runnable {
-   public:
-    explicit SendCallbackHandler(UDPSocketWrapper* delegate,
-                                 const ErrorCallback& forward_callback);
-    ~SendCallbackHandler() override;
-
-    // ErrorCallback::Runnable implementation:
-    void Run(NetworkErrorPtr result) const override;
-
-   private:
-    // Because this callback is passed to a method of |socket_|, and |socket_|
-    // is owned by |delegate_|, it should be safe to assume that |delegate_| is
-    // valid if/when Run() is called.
-    UDPSocketWrapper* delegate_;
-    ErrorCallback forward_callback_;
-  };
-
-  struct ReceivedData {
-    ReceivedData();
-    ~ReceivedData();
-
-    NetworkErrorPtr result;
-    NetAddressPtr src_addr;
-    Array<uint8_t> data;
-  };
-
-  struct SendRequest {
-    SendRequest();
-    ~SendRequest();
-
-    NetAddressPtr dest_addr;
-    Array<uint8_t> data;
-    ErrorCallback callback;
-  };
-
-  // UDPSocketClient implementation:
-  void OnReceived(NetworkErrorPtr result,
-                  NetAddressPtr src_addr,
-                  Array<uint8_t> data) override;
-
-  void Initialize(uint32_t requested_max_pending_sends);
-  void OnNegotiateMaxPendingSendRequestsCompleted(uint32_t actual_size);
-
-  void OnSendToCompleted(NetworkErrorPtr result,
-                         const ErrorCallback& forward_callback);
-
-  // Returns true if a send request in |send_requests_| has been processed.
-  bool ProcessNextSendRequest();
-
-  UDPSocketPtr socket_;
-
-  uint32_t max_receive_queue_size_;
-
-  // Owns all the objects that its elements point to.
-  std::queue<ReceivedData*> receive_queue_;
-
-  std::queue<ReceiveCallback> receive_requests_;
-
-  uint32_t max_pending_sends_;
-  uint32_t current_pending_sends_;
-
-  // Owns all the objects that its elements point to.
-  std::queue<SendRequest*> send_requests_;
-};
-
-}  // namespace mojo
-
-#endif  // MOJO_SERVICES_PUBLIC_CPP_NETWORK_UDP_SOCKET_WRAPPER_H_