Update boost to 1.71 and add asio

boost/asio/detail/executor_function.hpp

@@ -0,0 +1,106 @@
+//
+// detail/executor_function.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 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_EXECUTOR_FUNCTION_HPP
+#define BOOST_ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include <boost/asio/detail/config.hpp>
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+
+#include <boost/asio/detail/push_options.hpp>
+
+namespace boost {
+namespace asio {
+namespace detail {
+
+class executor_function_base
+{
+public:
+  void complete()
+  {
+    func_(this, true);
+  }
+
+  void destroy()
+  {
+    func_(this, false);
+  }
+
+protected:
+  typedef void (*func_type)(executor_function_base*, bool);
+
+  executor_function_base(func_type func)
+    : func_(func)
+  {
+  }
+
+  // Prevents deletion through this type.
+  ~executor_function_base()
+  {
+  }
+
+private:
+  func_type func_;
+};
+
+template <typename Function, typename Alloc>
+class executor_function : public executor_function_base
+{
+public:
+  BOOST_ASIO_DEFINE_TAGGED_HANDLER_ALLOCATOR_PTR(
+      thread_info_base::executor_function_tag, executor_function);
+
+  template <typename F>
+  executor_function(BOOST_ASIO_MOVE_ARG(F) f, const Alloc& allocator)
+    : executor_function_base(&executor_function::do_complete),
+      function_(BOOST_ASIO_MOVE_CAST(F)(f)),
+      allocator_(allocator)
+  {
+  }
+
+  static void do_complete(executor_function_base* base, bool call)
+  {
+    // Take ownership of the function object.
+    executor_function* o(static_cast<executor_function*>(base));
+    Alloc allocator(o->allocator_);
+    ptr p = { detail::addressof(allocator), o, o };
+
+    // Make a copy of the function so that the memory can be deallocated before
+    // the upcall is made. Even if we're not about to make an upcall, a
+    // sub-object of the function may be the true owner of the memory
+    // associated with the function. Consequently, a local copy of the function
+    // is required to ensure that any owning sub-object remains valid until
+    // after we have deallocated the memory here.
+    Function function(BOOST_ASIO_MOVE_CAST(Function)(o->function_));
+    p.reset();
+
+    // Make the upcall if required.
+    if (call)
+    {
+      function();
+    }
+  }
+
+private:
+  Function function_;
+  Alloc allocator_;
+};
+
+} // namespace detail
+} // namespace asio
+} // namespace boost
+
+#include <boost/asio/detail/pop_options.hpp>
+
+#endif // BOOST_ASIO_DETAIL_EXECUTOR_FUNCTION_HPP