ceph/src/boost/libs/asio/example/cpp03/local/connect_pair.cpp

   1 //
   2 // connect_pair.cpp
   3 // ~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #include <iostream>
  12 #include <string>
  13 #include <cctype>
  14 #include <boost/asio.hpp>
  15 #include <boost/thread/thread.hpp>
  16 #include <boost/array.hpp>
  17 #include <boost/bind.hpp>
  18
  19 #if defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
  20
  21 using boost::asio::local::stream_protocol;
  22
  23 class uppercase_filter
  24 {
  25 public:
  26   uppercase_filter(boost::asio::io_service& io_service)
  27     : socket_(io_service)
  28   {
  29   }
  30
  31   stream_protocol::socket& socket()
  32   {
  33     return socket_;
  34   }
  35
  36   void start()
  37   {
  38     // Wait for request.
  39     socket_.async_read_some(boost::asio::buffer(data_),
  40         boost::bind(&uppercase_filter::handle_read,
  41           this, boost::asio::placeholders::error,
  42           boost::asio::placeholders::bytes_transferred));
  43   }
  44
  45 private:
  46   void handle_read(const boost::system::error_code& ec, std::size_t size)
  47   {
  48     if (!ec)
  49     {
  50       // Compute result.
  51       for (std::size_t i = 0; i < size; ++i)
  52         data_[i] = std::toupper(data_[i]);
  53
  54       // Send result.
  55       boost::asio::async_write(socket_, boost::asio::buffer(data_, size),
  56           boost::bind(&uppercase_filter::handle_write,
  57             this, boost::asio::placeholders::error));
  58     }
  59     else
  60     {
  61       throw boost::system::system_error(ec);
  62     }
  63   }
  64
  65   void handle_write(const boost::system::error_code& ec)
  66   {
  67     if (!ec)
  68     {
  69       // Wait for request.
  70       socket_.async_read_some(boost::asio::buffer(data_),
  71           boost::bind(&uppercase_filter::handle_read,
  72             this, boost::asio::placeholders::error,
  73             boost::asio::placeholders::bytes_transferred));
  74     }
  75     else
  76     {
  77       throw boost::system::system_error(ec);
  78     }
  79   }
  80
  81   stream_protocol::socket socket_;
  82   boost::array<char, 512> data_;
  83 };
  84
  85 void run(boost::asio::io_service* io_service)
  86 {
  87   try
  88   {
  89     io_service->run();
  90   }
  91   catch (std::exception& e)
  92   {
  93     std::cerr << "Exception in thread: " << e.what() << "\n";
  94     std::exit(1);
  95   }
  96 }
  97
  98 int main()
  99 {
 100   try
 101   {
 102     boost::asio::io_service io_service;
 103
 104     // Create filter and establish a connection to it.
 105     uppercase_filter filter(io_service);
 106     stream_protocol::socket socket(io_service);
 107     boost::asio::local::connect_pair(socket, filter.socket());
 108     filter.start();
 109
 110     // The io_service runs in a background thread to perform filtering.
 111     boost::thread thread(boost::bind(run, &io_service));
 112
 113     for (;;)
 114     {
 115       // Collect request from user.
 116       std::cout << "Enter a string: ";
 117       std::string request;
 118       std::getline(std::cin, request);
 119
 120       // Send request to filter.
 121       boost::asio::write(socket, boost::asio::buffer(request));
 122
 123       // Wait for reply from filter.
 124       std::vector<char> reply(request.size());
 125       boost::asio::read(socket, boost::asio::buffer(reply));
 126
 127       // Show reply to user.
 128       std::cout << "Result: ";
 129       std::cout.write(&reply[0], request.size());
 130       std::cout << std::endl;
 131     }
 132   }
 133   catch (std::exception& e)
 134   {
 135     std::cerr << "Exception: " << e.what() << "\n";
 136     std::exit(1);
 137   }
 138 }
 139
 140 #else // defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)
 141 # error Local sockets not available on this platform.
 142 #endif // defined(BOOST_ASIO_HAS_LOCAL_SOCKETS)