De-Clientize UDPSocket service

mojo/services/network/public/cpp/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_NETWORK_PUBLIC_CPP_UDP_SOCKET_WRAPPER_H_
 #define MOJO_SERVICES_NETWORK_PUBLIC_CPP_UDP_SOCKET_WRAPPER_H_
 
 #include <queue>
 
 #include "network/public/interfaces/udp_socket.mojom.h"
+#include "third_party/mojo/src/mojo/public/cpp/bindings/binding.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 {
+class UDPSocketWrapper : public UDPSocketReceiver {
  public:
-  typedef Callback<void(NetworkErrorPtr, NetAddressPtr, Array<uint8_t>)>
-      ReceiveCallback;
-  typedef Callback<void(NetworkErrorPtr)> ErrorCallback;
+  using ReceiveCallback =
+      Callback<void(NetworkErrorPtr, NetAddressPtr, Array<uint8_t>)>;
+  using ErrorCallback = Callback<void(NetworkErrorPtr)>;
+  using BindOrConnectCallback =
+      Callback<void(NetworkErrorPtr,
+                    NetAddressPtr,
+                    InterfaceRequest<UDPSocketReceiver>)>;
 
   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,
@@ skipping 55 matching lines @@
     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_;
   };
 
+  class ReceiverBindingCallback : public BindOrConnectCallback::Runnable {
+   public:
+    ReceiverBindingCallback(
+        UDPSocketWrapper* delegate,
+        const Callback<void(NetworkErrorPtr, NetAddressPtr)>& wrapper_callback);
+    ~ReceiverBindingCallback() override;
+
+    // BindOrConnectCallback::Runnable implementation:
+    void Run(NetworkErrorPtr result,
+             NetAddressPtr addr,
+             InterfaceRequest<UDPSocketReceiver> request) 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_;
+    const Callback<void(NetworkErrorPtr, NetAddressPtr)> wrapper_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:
+  // UDPSocketReceiver 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();
 
+  // Binds to a UDPSocketReceiver request and notifies |socket_| that we're
+  // ready to start receiving data.
+  void StartReceivingData(InterfaceRequest<UDPSocketReceiver> request);
+
+  Binding<UDPSocketReceiver> binding_;
+
   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_NETWORK_PUBLIC_CPP_UDP_SOCKET_WRAPPER_H_