1 files changed, 82 insertions, 0 deletions
diff --git a/boost/asio/detail/posix_global.hpp b/boost/asio/detail/posix_global.hpp
new file mode 100644
index 0000000000..463809fc29
--- /dev/null
+++ b/boost/asio/detail/posix_global.hpp
@@ -0,0 +1,82 @@
+//
+// detail/posix_global.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2017 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BOOST_ASIO_DETAIL_POSIX_GLOBAL_HPP
+#define BOOST_ASIO_DETAIL_POSIX_GLOBAL_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+
+#if defined(BOOST_ASIO_HAS_PTHREADS)
+
+#include <exception>
+#include <pthread.h>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+template <typename T>
+struct posix_global_impl
+{
+  // Helper function to perform initialisation.
+  static void do_init()
+  {
+    instance_.static_ptr_ = instance_.ptr_ = new T;
+  }
+
+  // Destructor automatically cleans up the global.
+  ~posix_global_impl()
+  {
+    delete static_ptr_;
+  }
+
+  static ::pthread_once_t init_once_;
+  static T* static_ptr_;
+  static posix_global_impl instance_;
+  T* ptr_;
+};
+
+template <typename T>
+::pthread_once_t posix_global_impl<T>::init_once_ = PTHREAD_ONCE_INIT;
+
+template <typename T>
+T* posix_global_impl<T>::static_ptr_ = 0;
+
+template <typename T>
+posix_global_impl<T> posix_global_impl<T>::instance_;
+
+template <typename T>
+T& posix_global()
+{
+  int result = ::pthread_once(
+      &posix_global_impl<T>::init_once_,
+      &posix_global_impl<T>::do_init);
+
+  if (result != 0)
+    std::terminate();
+
+  return *posix_global_impl<T>::instance_.ptr_;
+}
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_PTHREADS)
+
+#endif // BOOST_ASIO_DETAIL_POSIX_GLOBAL_HPP