Initial Commit

include/asio/detail/impl/strand_service.hpp

@@ -0,0 +1,86 @@
+//
+// detail/impl/strand_service.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2025 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 ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP
+#define ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include "asio/detail/completion_handler.hpp"
+#include "asio/detail/fenced_block.hpp"
+#include "asio/detail/handler_alloc_helpers.hpp"
+#include "asio/detail/memory.hpp"
+
+#include "asio/detail/push_options.hpp"
+
+namespace asio {
+namespace detail {
+
+inline strand_service::strand_impl::strand_impl()
+  : operation(&strand_service::do_complete),
+    locked_(false)
+{
+}
+
+template <typename Handler>
+void strand_service::dispatch(strand_service::implementation_type& impl,
+    Handler& handler)
+{
+  // If we are already in the strand then the handler can run immediately.
+  if (running_in_this_thread(impl))
+  {
+    fenced_block b(fenced_block::full);
+    static_cast<Handler&&>(handler)();
+    return;
+  }
+
+  // Allocate and construct an operation to wrap the handler.
+  typedef completion_handler<Handler, io_context::executor_type> op;
+  typename op::ptr p = { asio::detail::addressof(handler),
+    op::ptr::allocate(handler), 0 };
+  p.p = new (p.v) op(handler, io_context_.get_executor());
+
+  ASIO_HANDLER_CREATION((this->context(),
+        *p.p, "strand", impl, 0, "dispatch"));
+
+  operation* o = p.p;
+  p.v = p.p = 0;
+  do_dispatch(impl, o);
+}
+
+// Request the io_context to invoke the given handler and return immediately.
+template <typename Handler>
+void strand_service::post(strand_service::implementation_type& impl,
+    Handler& handler)
+{
+  bool is_continuation =
+    asio_handler_cont_helpers::is_continuation(handler);
+
+  // Allocate and construct an operation to wrap the handler.
+  typedef completion_handler<Handler, io_context::executor_type> op;
+  typename op::ptr p = { asio::detail::addressof(handler),
+    op::ptr::allocate(handler), 0 };
+  p.p = new (p.v) op(handler, io_context_.get_executor());
+
+  ASIO_HANDLER_CREATION((this->context(),
+        *p.p, "strand", impl, 0, "post"));
+
+  do_post(impl, p.p, is_continuation);
+  p.v = p.p = 0;
+}
+
+} // namespace detail
+} // namespace asio
+
+#include "asio/detail/pop_options.hpp"
+
+#endif // ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP