1 files changed, 118 insertions, 0 deletions
diff --git a/lib/asio/detail/impl/strand_service.hpp b/lib/asio/detail/impl/strand_service.hpp
new file mode 100644
index 0000000..da5b716
--- /dev/null
+++ b/lib/asio/detail/impl/strand_service.hpp
@@ -0,0 +1,118 @@
+//
+// detail/impl/strand_service.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 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/call_stack.hpp"
+#include "asio/detail/completion_handler.hpp"
+#include "asio/detail/fenced_block.hpp"
+#include "asio/detail/handler_alloc_helpers.hpp"
+#include "asio/detail/handler_invoke_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)
+{
+}
+
+struct strand_service::on_dispatch_exit
+{
+  io_context_impl* io_context_;
+  strand_impl* impl_;
+
+  ~on_dispatch_exit()
+  {
+    impl_->mutex_.lock();
+    impl_->ready_queue_.push(impl_->waiting_queue_);
+    bool more_handlers = impl_->locked_ = !impl_->ready_queue_.empty();
+    impl_->mutex_.unlock();
+
+    if (more_handlers)
+      io_context_->post_immediate_completion(impl_, 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 (call_stack<strand_impl>::contains(impl))
+  {
+    fenced_block b(fenced_block::full);
+    asio_handler_invoke_helpers::invoke(handler, handler);
+    return;
+  }
+
+  // Allocate and construct an operation to wrap the handler.
+  typedef completion_handler<Handler> op;
+  typename op::ptr p = { asio::detail::addressof(handler),
+    op::ptr::allocate(handler), 0 };
+  p.p = new (p.v) op(handler);
+
+  ASIO_HANDLER_CREATION((this->context(),
+        *p.p, "strand", impl, 0, "dispatch"));
+
+  bool dispatch_immediately = do_dispatch(impl, p.p);
+  operation* o = p.p;
+  p.v = p.p = 0;
+
+  if (dispatch_immediately)
+  {
+    // Indicate that this strand is executing on the current thread.
+    call_stack<strand_impl>::context ctx(impl);
+
+    // Ensure the next handler, if any, is scheduled on block exit.
+    on_dispatch_exit on_exit = { &io_context_, impl };
+    (void)on_exit;
+
+    completion_handler<Handler>::do_complete(
+        &io_context_, o, asio::error_code(), 0);
+  }
+}
+
+// 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> op;
+  typename op::ptr p = { asio::detail::addressof(handler),
+    op::ptr::allocate(handler), 0 };
+  p.p = new (p.v) op(handler);
+
+  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