1 /*
2  * Copyright (C) 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <functional>
20 #include <memory>
21 #include <thread>
22 
23 #include "common/libs/fs/shared_fd.h"
24 
25 namespace cuttlefish {
26 
27 class ProxyServer {
28  public:
29   ProxyServer(SharedFD server, std::function<SharedFD()> clients_factory);
30   void Join();
31   ~ProxyServer();
32 
33  private:
34   SharedFD stop_fd_;
35   std::thread server_;
36 };
37 
38 // Executes a TCP proxy
39 // Accept() is called on the server in a loop, for every client connection a
40 // target connection is created through the conn_factory callback and data is
41 // forwarded between the two connections.
42 // This function is meant to execute forever, but will return if the server is
43 // closed in another thread. It's recommended the caller disables the default
44 // behavior for SIGPIPE before calling this function, otherwise it runs the risk
45 // or crashing the process when a connection breaks.
46 void Proxy(SharedFD server, std::function<SharedFD()> conn_factory);
47 std::unique_ptr<ProxyServer> ProxyAsync(SharedFD server, std::function<SharedFD()> conn_factory);
48 
49 }  // namespace cuttlefish
50