libs/asio/example/cpp03/windows/transmit_file.cpp

   1 //
   2 // transmit_file.cpp
   3 // ~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2014 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 <ctime>
  12 #include <iostream>
  13 #include <string>
  14 #include <boost/bind.hpp>
  15 #include <boost/shared_ptr.hpp>
  16 #include <boost/enable_shared_from_this.hpp>
  17 #include <boost/asio.hpp>
  18
  19 #if defined(BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
  20
  21 using boost::asio::ip::tcp;
  22 using boost::asio::windows::overlapped_ptr;
  23 using boost::asio::windows::random_access_handle;
  24
  25 // A wrapper for the TransmitFile overlapped I/O operation.
  26 template <typename Handler>
  27 void transmit_file(tcp::socket& socket,
  28     random_access_handle& file, Handler handler)
  29 {
  30   // Construct an OVERLAPPED-derived object to contain the handler.
  31   overlapped_ptr overlapped(socket.get_io_service(), handler);
  32
  33   // Initiate the TransmitFile operation.
  34   BOOL ok = ::TransmitFile(socket.native_handle(),
  35       file.native_handle(), 0, 0, overlapped.get(), 0, 0);
  36   DWORD last_error = ::GetLastError();
  37
  38   // Check if the operation completed immediately.
  39   if (!ok && last_error != ERROR_IO_PENDING)
  40   {
  41     // The operation completed immediately, so a completion notification needs
  42     // to be posted. When complete() is called, ownership of the OVERLAPPED-
  43     // derived object passes to the io_service.
  44     boost::system::error_code ec(last_error,
  45         boost::asio::error::get_system_category());
  46     overlapped.complete(ec, 0);
  47   }
  48   else
  49   {
  50     // The operation was successfully initiated, so ownership of the
  51     // OVERLAPPED-derived object has passed to the io_service.
  52     overlapped.release();
  53   }
  54 }
  55
  56 class connection
  57   : public boost::enable_shared_from_this<connection>
  58 {
  59 public:
  60   typedef boost::shared_ptr<connection> pointer;
  61
  62   static pointer create(boost::asio::io_service& io_service,
  63       const std::string& filename)
  64   {
  65     return pointer(new connection(io_service, filename));
  66   }
  67
  68   tcp::socket& socket()
  69   {
  70     return socket_;
  71   }
  72
  73   void start()
  74   {
  75     boost::system::error_code ec;
  76     file_.assign(::CreateFile(filename_.c_str(), GENERIC_READ, 0, 0,
  77           OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED, 0), ec);
  78     if (file_.is_open())
  79     {
  80       transmit_file(socket_, file_,
  81           boost::bind(&connection::handle_write, shared_from_this(),
  82             boost::asio::placeholders::error,
  83             boost::asio::placeholders::bytes_transferred));
  84     }
  85   }
  86
  87 private:
  88   connection(boost::asio::io_service& io_service, const std::string& filename)
  89     : socket_(io_service),
  90       filename_(filename),
  91       file_(io_service)
  92   {
  93   }
  94
  95   void handle_write(const boost::system::error_code& /*error*/,
  96       size_t /*bytes_transferred*/)
  97   {
  98     boost::system::error_code ignored_ec;
  99     socket_.shutdown(tcp::socket::shutdown_both, ignored_ec);
 100   }
 101
 102   tcp::socket socket_;
 103   std::string filename_;
 104   random_access_handle file_;
 105 };
 106
 107 class server
 108 {
 109 public:
 110   server(boost::asio::io_service& io_service,
 111       unsigned short port, const std::string& filename)
 112     : acceptor_(io_service, tcp::endpoint(tcp::v4(), port)),
 113       filename_(filename)
 114   {
 115     start_accept();
 116   }
 117
 118 private:
 119   void start_accept()
 120   {
 121     connection::pointer new_connection =
 122       connection::create(acceptor_.get_io_service(), filename_);
 123
 124     acceptor_.async_accept(new_connection->socket(),
 125         boost::bind(&server::handle_accept, this, new_connection,
 126           boost::asio::placeholders::error));
 127   }
 128
 129   void handle_accept(connection::pointer new_connection,
 130       const boost::system::error_code& error)
 131   {
 132     if (!error)
 133     {
 134       new_connection->start();
 135     }
 136
 137     start_accept();
 138   }
 139
 140   tcp::acceptor acceptor_;
 141   std::string filename_;
 142 };
 143
 144 int main(int argc, char* argv[])
 145 {
 146   try
 147   {
 148     if (argc != 3)
 149     {
 150       std::cerr << "Usage: transmit_file <port> <filename>\n";
 151       return 1;
 152     }
 153
 154     boost::asio::io_service io_service;
 155
 156     using namespace std; // For atoi.
 157     server s(io_service, atoi(argv[1]), argv[2]);
 158
 159     io_service.run();
 160   }
 161   catch (std::exception& e)
 162   {
 163     std::cerr << e.what() << std::endl;
 164   }
 165
 166   return 0;
 167 }
 168
 169 #else // defined(BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
 170 # error Overlapped I/O not available on this platform
 171 #endif // defined(BOOST_ASIO_HAS_WINDOWS_OVERLAPPED_PTR)