*** a/boost/asio/datagram_socket_service.hpp	2013-09-22 15:13:33.000000000 -0700
--- b/boost/asio/datagram_socket_service.hpp	2014-05-06 04:20:40.438047289 -0700
***************
*** 22,27 ****
--- 22,31 ----
  #include <boost/asio/error.hpp>
  #include <boost/asio/io_service.hpp>
  
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+ # include <boost/asio/detail/mutex.hpp>
+ #endif
+ 
  #if defined(BOOST_ASIO_WINDOWS_RUNTIME)
  # include <boost/asio/detail/null_socket_service.hpp>
  #elif defined(BOOST_ASIO_HAS_IOCP)
***************
*** 135,140 ****
--- 139,147 ----
    /// Destroy a datagram socket implementation.
    void destroy(implementation_type& impl)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.destroy(impl);
    }
  
***************
*** 167,172 ****
--- 174,182 ----
    boost::system::error_code close(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.close(impl, ec);
    }
  
***************
*** 186,191 ****
--- 196,204 ----
    boost::system::error_code cancel(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.cancel(impl, ec);
    }
  
***************
*** 225,230 ****
--- 238,246 ----
        const endpoint_type& peer_endpoint,
        BOOST_ASIO_MOVE_ARG(ConnectHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ConnectHandler, void (boost::system::error_code)> init(
          BOOST_ASIO_MOVE_CAST(ConnectHandler)(handler));
***************
*** 322,327 ****
--- 338,346 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 349,354 ****
--- 368,376 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 377,382 ****
--- 399,407 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 405,410 ****
--- 430,438 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 424,429 ****
--- 452,462 ----
  
    // The platform-specific implementation.
    service_impl_type service_impl_;
+ 
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+   // Per-socket lock used to make the socket service thread-safe
+   detail::mutex mutex_;
+ #endif
  };
  
  } // namespace asio
*** a/boost/asio/raw_socket_service.hpp	2013-09-22 15:13:33.000000000 -0700
--- b/boost/asio/raw_socket_service.hpp	2014-05-06 04:16:26.274052726 -0700
***************
*** 22,27 ****
--- 22,31 ----
  #include <boost/asio/error.hpp>
  #include <boost/asio/io_service.hpp>
  
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+ # include <boost/asio/detail/mutex.hpp>
+ #endif
+ 
  #if defined(BOOST_ASIO_WINDOWS_RUNTIME)
  # include <boost/asio/detail/null_socket_service.hpp>
  #elif defined(BOOST_ASIO_HAS_IOCP)
***************
*** 167,172 ****
--- 171,179 ----
    boost::system::error_code close(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.close(impl, ec);
    }
  
***************
*** 186,191 ****
--- 193,201 ----
    boost::system::error_code cancel(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.cancel(impl, ec);
    }
  
***************
*** 225,230 ****
--- 235,243 ----
        const endpoint_type& peer_endpoint,
        BOOST_ASIO_MOVE_ARG(ConnectHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ConnectHandler, void (boost::system::error_code)> init(
          BOOST_ASIO_MOVE_CAST(ConnectHandler)(handler));
***************
*** 302,307 ****
--- 315,323 ----
    boost::system::error_code shutdown(implementation_type& impl,
        socket_base::shutdown_type what, boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.shutdown(impl, what, ec);
    }
  
***************
*** 322,327 ****
--- 338,346 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 349,354 ****
--- 368,376 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 377,382 ****
--- 399,407 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 405,410 ****
--- 430,438 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 419,429 ****
--- 447,465 ----
    // Destroy all user-defined handler objects owned by the service.
    void shutdown_service()
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.shutdown_service();
    }
  
    // The platform-specific implementation.
    service_impl_type service_impl_;
+ 
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+   // Per-socket lock used to make the socket service thread-safe
+   detail::mutex mutex_;
+ #endif
  };
  
  } // namespace asio
*** a/boost/asio/seq_packet_socket_service.hpp	2013-09-22 15:13:33.000000000 -0700
--- b/boost/asio/seq_packet_socket_service.hpp	2014-05-06 04:16:26.274052726 -0700
***************
*** 22,27 ****
--- 22,31 ----
  #include <boost/asio/error.hpp>
  #include <boost/asio/io_service.hpp>
  
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+ # include <boost/asio/detail/mutex.hpp>
+ #endif
+ 
  #if defined(BOOST_ASIO_WINDOWS_RUNTIME)
  # include <boost/asio/detail/null_socket_service.hpp>
  #elif defined(BOOST_ASIO_HAS_IOCP)
***************
*** 137,142 ****
--- 141,149 ----
    /// Destroy a sequenced packet socket implementation.
    void destroy(implementation_type& impl)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.destroy(impl);
    }
  
***************
*** 169,174 ****
--- 176,184 ----
    boost::system::error_code close(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.close(impl, ec);
    }
  
***************
*** 188,193 ****
--- 198,206 ----
    boost::system::error_code cancel(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.cancel(impl, ec);
    }
  
***************
*** 227,232 ****
--- 240,248 ----
        const endpoint_type& peer_endpoint,
        BOOST_ASIO_MOVE_ARG(ConnectHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ConnectHandler, void (boost::system::error_code)> init(
          BOOST_ASIO_MOVE_CAST(ConnectHandler)(handler));
***************
*** 304,309 ****
--- 320,328 ----
    boost::system::error_code shutdown(implementation_type& impl,
        socket_base::shutdown_type what, boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.shutdown(impl, what, ec);
    }
  
***************
*** 325,330 ****
--- 344,352 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 353,358 ****
--- 375,383 ----
        socket_base::message_flags& out_flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 367,377 ****
--- 392,410 ----
    // Destroy all user-defined handler objects owned by the service.
    void shutdown_service()
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.shutdown_service();
    }
  
    // The platform-specific implementation.
    service_impl_type service_impl_;
+ 
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+   // Per-socket lock used to make the socket service thread-safe
+   detail::mutex mutex_;
+ #endif
  };
  
  } // namespace asio
*** a/boost/asio/stream_socket_service.hpp	2013-09-22 15:13:33.000000000 -0700
--- b/boost/asio/stream_socket_service.hpp	2014-05-06 04:16:26.274052726 -0700
***************
*** 22,27 ****
--- 22,31 ----
  #include <boost/asio/error.hpp>
  #include <boost/asio/io_service.hpp>
  
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+ # include <boost/asio/detail/mutex.hpp>
+ #endif
+ 
  #if defined(BOOST_ASIO_WINDOWS_RUNTIME)
  # include <boost/asio/detail/winrt_ssocket_service.hpp>
  #elif defined(BOOST_ASIO_HAS_IOCP)
***************
*** 135,140 ****
--- 139,147 ----
    /// Destroy a stream socket implementation.
    void destroy(implementation_type& impl)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.destroy(impl);
    }
  
***************
*** 167,172 ****
--- 174,182 ----
    boost::system::error_code close(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.close(impl, ec);
    }
  
***************
*** 186,191 ****
--- 196,204 ----
    boost::system::error_code cancel(implementation_type& impl,
        boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.cancel(impl, ec);
    }
  
***************
*** 225,230 ****
--- 238,246 ----
        const endpoint_type& peer_endpoint,
        BOOST_ASIO_MOVE_ARG(ConnectHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ConnectHandler, void (boost::system::error_code)> init(
          BOOST_ASIO_MOVE_CAST(ConnectHandler)(handler));
***************
*** 302,307 ****
--- 318,326 ----
    boost::system::error_code shutdown(implementation_type& impl,
        socket_base::shutdown_type what, boost::system::error_code& ec)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      return service_impl_.shutdown(impl, what, ec);
    }
  
***************
*** 323,328 ****
--- 342,350 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(WriteHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        WriteHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(WriteHandler)(handler));
***************
*** 350,355 ****
--- 372,380 ----
        socket_base::message_flags flags,
        BOOST_ASIO_MOVE_ARG(ReadHandler) handler)
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      detail::async_result_init<
        ReadHandler, void (boost::system::error_code, std::size_t)> init(
          BOOST_ASIO_MOVE_CAST(ReadHandler)(handler));
***************
*** 363,373 ****
--- 388,406 ----
    // Destroy all user-defined handler objects owned by the service.
    void shutdown_service()
    {
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+     detail::mutex::scoped_lock lock(mutex_);
+ #endif
      service_impl_.shutdown_service();
    }
  
    // The platform-specific implementation.
    service_impl_type service_impl_;
+ 
+ #if defined(BOOST_ASIO_THREAD_SAFE_SOCKET_SERVICES)
+   // Per-socket lock used to make the socket service thread-safe
+   detail::mutex mutex_;
+ #endif
  };
  
  } // namespace asio