boost/asio/detail/win_mutex.hpp

   1 //
   2 // win_mutex.hpp
   3 // ~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2008 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 BOOST_ASIO_DETAIL_WIN_MUTEX_HPP
  12 #define BOOST_ASIO_DETAIL_WIN_MUTEX_HPP
  13
  14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  15 # pragma once
  16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  17
  18 #include <boost/asio/detail/push_options.hpp>
  19
  20 #include <boost/asio/detail/push_options.hpp>
  21 #include <boost/config.hpp>
  22 #include <boost/system/system_error.hpp>
  23 #include <boost/asio/detail/pop_options.hpp>
  24
  25 #if defined(BOOST_WINDOWS)
  26
  27 #include <boost/asio/error.hpp>
  28 #include <boost/asio/detail/noncopyable.hpp>
  29 #include <boost/asio/detail/socket_types.hpp>
  30 #include <boost/asio/detail/scoped_lock.hpp>
  31
  32 #include <boost/asio/detail/push_options.hpp>
  33 #include <boost/throw_exception.hpp>
  34 #include <boost/asio/detail/pop_options.hpp>
  35
  36 namespace boost {
  37 namespace asio {
  38 namespace detail {
  39
  40 class win_mutex
  41   : private noncopyable
  42 {
  43 public:
  44   typedef boost::asio::detail::scoped_lock<win_mutex> scoped_lock;
  45
  46   // Constructor.
  47   win_mutex()
  48   {
  49     int error = do_init();
  50     if (error != 0)
  51     {
  52       boost::system::system_error e(
  53           boost::system::error_code(error,
  54             boost::asio::error::get_system_category()),
  55           "mutex");
  56       boost::throw_exception(e);
  57     }
  58   }
  59
  60   // Destructor.
  61   ~win_mutex()
  62   {
  63     ::DeleteCriticalSection(&crit_section_);
  64   }
  65
  66   // Lock the mutex.
  67   void lock()
  68   {
  69     int error = do_lock();
  70     if (error != 0)
  71     {
  72       boost::system::system_error e(
  73           boost::system::error_code(error,
  74             boost::asio::error::get_system_category()),
  75           "mutex");
  76       boost::throw_exception(e);
  77     }
  78   }
  79
  80   // Unlock the mutex.
  81   void unlock()
  82   {
  83     ::LeaveCriticalSection(&crit_section_);
  84   }
  85
  86 private:
  87   // Initialisation must be performed in a separate function to the constructor
  88   // since the compiler does not support the use of structured exceptions and
  89   // C++ exceptions in the same function.
  90   int do_init()
  91   {
  92 #if defined(__MINGW32__)
  93     // Not sure if MinGW supports structured exception handling, so for now
  94     // we'll just call the Windows API and hope.
  95     ::InitializeCriticalSection(&crit_section_);
  96     return 0;
  97 #else
  98     __try
  99     {
 100       ::InitializeCriticalSection(&crit_section_);
 101     }
 102     __except(GetExceptionCode() == STATUS_NO_MEMORY
 103         ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
 104     {
 105       return ERROR_OUTOFMEMORY;
 106     }
 107
 108     return 0;
 109 #endif
 110   }
 111
 112   // Locking must be performed in a separate function to lock() since the
 113   // compiler does not support the use of structured exceptions and C++
 114   // exceptions in the same function.
 115   int do_lock()
 116   {
 117 #if defined(__MINGW32__)
 118     // Not sure if MinGW supports structured exception handling, so for now
 119     // we'll just call the Windows API and hope.
 120     ::EnterCriticalSection(&crit_section_);
 121     return 0;
 122 #else
 123     __try
 124     {
 125       ::EnterCriticalSection(&crit_section_);
 126     }
 127     __except(GetExceptionCode() == STATUS_INVALID_HANDLE
 128         || GetExceptionCode() == STATUS_NO_MEMORY
 129         ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
 130     {
 131       if (GetExceptionCode() == STATUS_NO_MEMORY)
 132         return ERROR_OUTOFMEMORY;
 133       return ERROR_INVALID_HANDLE;
 134     }
 135
 136     return 0;
 137 #endif
 138   }
 139
 140   ::CRITICAL_SECTION crit_section_;
 141 };
 142
 143 } // namespace detail
 144 } // namespace asio
 145 } // namespace boost
 146
 147 #endif // defined(BOOST_WINDOWS)
 148
 149 #include <boost/asio/detail/pop_options.hpp>
 150
 151 #endif // BOOST_ASIO_DETAIL_WIN_MUTEX_HPP