Imported Upstream version 1.66.0upstream/1.66.0

1 files changed, 128 insertions, 0 deletions

diff --git a/boost/asio/packaged_task.hpp b/boost/asio/packaged_task.hpp
new file mode 100644
index 0000000000..586de13b7b
--- /dev/null
+++ b/boost/asio/packaged_task.hpp
@@ -0,0 +1,128 @@
+//
+// packaged_task.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_PACKAGED_TASK_HPP
+#define BOOST_ASIO_PACKAGED_TASK_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_STD_FUTURE) \
+  || defined(GENERATING_DOCUMENTATION)
+
+#include <future>
+#include <boost/asio/async_result.hpp>
+#include <boost/asio/detail/type_traits.hpp>
+#include <boost/asio/detail/variadic_templates.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+
+#if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES) \
+  || defined(GENERATING_DOCUMENTATION)
+
+/// Partial specialisation of @c async_result for @c std::packaged_task.
+template <typename Result, typename... Args, typename Signature>
+class async_result<std::packaged_task<Result(Args...)>, Signature>
+{
+public:
+  /// The packaged task is the concrete completion handler type.
+  typedef std::packaged_task<Result(Args...)> completion_handler_type;
+
+  /// The return type of the initiating function is the future obtained from
+  /// the packaged task.
+  typedef std::future<Result> return_type;
+
+  /// The constructor extracts the future from the packaged task.
+  explicit async_result(completion_handler_type& h)
+    : future_(h.get_future())
+  {
+  }
+
+  /// Returns the packaged task's future.
+  return_type get()
+  {
+    return std::move(future_);
+  }
+
+private:
+  return_type future_;
+};
+
+#else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+      //   || defined(GENERATING_DOCUMENTATION)
+
+template <typename Result, typename Signature>
+struct async_result<std::packaged_task<Result()>, Signature>
+{
+  typedef std::packaged_task<Result()> completion_handler_type;
+  typedef std::future<Result> return_type;
+
+  explicit async_result(completion_handler_type& h)
+    : future_(h.get_future())
+  {
+  }
+
+  return_type get()
+  {
+    return std::move(future_);
+  }
+
+private:
+  return_type future_;
+};
+
+#define BOOST_ASIO_PRIVATE_ASYNC_RESULT_DEF(n) \
+  template <typename Result, \
+    BOOST_ASIO_VARIADIC_TPARAMS(n), typename Signature> \
+  class async_result< \
+    std::packaged_task<Result(BOOST_ASIO_VARIADIC_TARGS(n))>, Signature> \
+  { \
+  public: \
+    typedef std::packaged_task< \
+      Result(BOOST_ASIO_VARIADIC_TARGS(n))> \
+        completion_handler_type; \
+  \
+    typedef std::future<Result> return_type; \
+  \
+    explicit async_result(completion_handler_type& h) \
+      : future_(h.get_future()) \
+    { \
+    } \
+  \
+    return_type get() \
+    { \
+      return std::move(future_); \
+    } \
+  \
+  private: \
+    return_type future_; \
+  }; \
+  /**/
+  BOOST_ASIO_VARIADIC_GENERATE(BOOST_ASIO_PRIVATE_ASYNC_RESULT_DEF)
+#undef BOOST_ASIO_PRIVATE_ASYNC_RESULT_DEF
+
+#endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
+       //   || defined(GENERATING_DOCUMENTATION)
+
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // defined(BOOST_ASIO_HAS_STD_FUTURE)
+       //   || defined(GENERATING_DOCUMENTATION)
+
+#endif // BOOST_ASIO_PACKAGED_TASK_HPP