gameserv-2.0/asio/asio/detail/winsock_init.hpp

   1 //
   2 // detail/winsock_init.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2011 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 #ifndef ASIO_DETAIL_WINSOCK_INIT_HPP
  12 #define ASIO_DETAIL_WINSOCK_INIT_HPP
  13
  14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  15 # pragma once
  16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  17
  18 #include "asio/detail/config.hpp"
  19
  20 #if defined(BOOST_WINDOWS) || defined(__CYGWIN__)
  21
  22 #include "asio/detail/push_options.hpp"
  23
  24 namespace asio {
  25 namespace detail {
  26
  27 class winsock_init_base
  28 {
  29 protected:
  30   // Structure to track result of initialisation and number of uses. POD is used
  31   // to ensure that the values are zero-initialised prior to any code being run.
  32   struct data
  33   {
  34     long init_count_;
  35     long result_;
  36   };
  37
  38   ASIO_DECL static void startup(data& d,
  39       unsigned char major, unsigned char minor);
  40
  41   ASIO_DECL static void cleanup(data& d);
  42
  43   ASIO_DECL static void throw_on_error(data& d);
  44 };
  45
  46 template <int Major = 2, int Minor = 0>
  47 class winsock_init : private winsock_init_base
  48 {
  49 public:
  50   winsock_init(bool allow_throw = true)
  51   {
  52     startup(data_, Major, Minor);
  53     if (allow_throw)
  54       throw_on_error(data_);
  55   }
  56
  57   winsock_init(const winsock_init&)
  58   {
  59     startup(data_, Major, Minor);
  60     throw_on_error(data_);
  61   }
  62
  63   ~winsock_init()
  64   {
  65     cleanup(data_);
  66   }
  67
  68 private:
  69   static data data_;
  70 };
  71
  72 template <int Major, int Minor>
  73 winsock_init_base::data winsock_init<Major, Minor>::data_;
  74
  75 // Static variable to ensure that winsock is initialised before main, and
  76 // therefore before any other threads can get started.
  77 static const winsock_init<>& winsock_init_instance = winsock_init<>(false);
  78
  79 } // namespace detail
  80 } // namespace asio
  81
  82 #include "asio/detail/pop_options.hpp"
  83
  84 #if defined(ASIO_HEADER_ONLY)
  85 # include "asio/detail/impl/winsock_init.ipp"
  86 #endif // defined(ASIO_HEADER_ONLY)
  87
  88 #endif // defined(BOOST_WINDOWS) || defined(__CYGWIN__)
  89
  90 #endif // ASIO_DETAIL_WINSOCK_INIT_HPP