EDK: Move DispatcherTransport to handle_transport.*.

mojo/edk/system/handle_transport.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MOJO_EDK_SYSTEM_HANDLE_TRANSPORT_H_
+#define MOJO_EDK_SYSTEM_HANDLE_TRANSPORT_H_
+
+#include "mojo/edk/system/dispatcher.h"
+#include "mojo/edk/util/ref_ptr.h"
+#include "mojo/edk/util/thread_annotations.h"
+
+namespace mojo {
+namespace system {
+
+class MessagePipe;
+
+// Wrapper around a |Dispatcher| pointer, while it's being processed to be
+// passed in a message pipe. See the comment about
+// |Dispatcher::HandleTableAccess| for more details.
+//
+// Note: This class is deliberately "thin" -- no more expensive than a
+// |Dispatcher*|.
+//
+// TODO(vtl): Add handle rights to this, and rename it to HandleTransport.
+class DispatcherTransport final {
+ public:
+  DispatcherTransport() : dispatcher_(nullptr) {}
+
+  void End() MOJO_NOT_THREAD_SAFE;
+
+  Dispatcher::Type GetType() const { return dispatcher_->GetType(); }
+  bool IsBusy() const MOJO_NOT_THREAD_SAFE {
+    return dispatcher_->IsBusyNoLock();
+  }
+  void Close() MOJO_NOT_THREAD_SAFE { dispatcher_->CloseNoLock(); }
+  util::RefPtr<Dispatcher> CreateEquivalentDispatcherAndClose(
+      MessagePipe* message_pipe,
+      unsigned port) MOJO_NOT_THREAD_SAFE {
+    return dispatcher_->CreateEquivalentDispatcherAndCloseNoLock(message_pipe,
+                                                                 port);
+  }
+
+  bool is_valid() const { return !!dispatcher_; }
+
+ private:
+  friend class Dispatcher::HandleTableAccess;
+
+  explicit DispatcherTransport(Dispatcher* dispatcher)
+      : dispatcher_(dispatcher) {}
+
+  Dispatcher* dispatcher_;
+
+  // Copy and assign allowed.
+};
+
+}  // namespace system
+}  // namespace mojo
+
+#endif  // MOJO_EDK_SYSTEM_HANDLE_TRANSPORT_H_