Update mojo sdk to rev e01f9a49449381a5eb430c1fd88bf2cae73ec35a

mojo/edk/system/channel_manager.h

+// Copyright 2014 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_CHANNEL_MANAGER_H_
+#define MOJO_EDK_SYSTEM_CHANNEL_MANAGER_H_
+
+#include <stdint.h>
+
+#include "base/containers/hash_tables.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "base/task_runner.h"
+#include "mojo/edk/system/channel.h"
+#include "mojo/edk/system/channel_info.h"
+
+namespace mojo {
+namespace system {
+
+// IDs for |Channel|s managed by a |ChannelManager|. (IDs should be thought of
+// as specific to a given |ChannelManager|.) 0 is never a valid ID.
+//
+// Note: We currently just use the pointer of the |Channel| casted to a
+// |uintptr_t|, but we reserve the right to change this.
+typedef uintptr_t ChannelId;
+
+// This class manages and "owns" |Channel|s (which typically connect to other
+// processes) for a given process. This class is thread-safe.
+class MOJO_SYSTEM_IMPL_EXPORT ChannelManager {
+ public:
+  ChannelManager();
+  ~ChannelManager();
+
+  // Gets the ID for a given channel.
+  //
+  // Note: This is currently a static method and thus may be called under
+  // |lock_|. If this is ever made non-static (i.e., made specific to a given
+  // |ChannelManager|), those call sites may have to changed.
+  static ChannelId GetChannelId(const Channel* channel) {
+    return reinterpret_cast<ChannelId>(channel);
+  }
+
+  // Adds |channel| to the set of |Channel|s managed by this |ChannelManager|;
+  // |channel_thread_task_runner| should be the task runner for |channel|'s
+  // creation (a.k.a. I/O) thread. |channel| should either already be
+  // initialized. It should not be managed by any |ChannelManager| yet. Returns
+  // the ID for the added channel.
+  ChannelId AddChannel(
+      scoped_refptr<Channel> channel,
+      scoped_refptr<base::TaskRunner> channel_thread_task_runner);
+
+  // Informs the channel manager (and thus channel) that it will be shutdown
+  // soon (by calling |ShutdownChannel()|). Calling this is optional (and may in
+  // fact be called multiple times) but it will suppress certain warnings (e.g.,
+  // for the channel being broken) and enable others (if messages are written to
+  // the channel).
+  void WillShutdownChannel(ChannelId channel_id);
+
+  // Shuts down the channel specified by the given ID. It is up to the caller to
+  // guarantee that this is only called once per channel (that was added using
+  // |AddChannel()|). If called from the chanel's creation thread (i.e.,
+  // |base::MessageLoopProxy::current()| is the channel thread's |TaskRunner|),
+  // this will complete synchronously.
+  void ShutdownChannel(ChannelId channel_id);
+
+ private:
+  // Gets the |ChannelInfo| for the channel specified by the given ID. (This
+  // should *not* be called under lock.)
+  ChannelInfo GetChannelInfo(ChannelId channel_id);
+
+  // Note: |Channel| methods should not be called under |lock_|.
+  base::Lock lock_;  // Protects the members below.
+
+  base::hash_map<ChannelId, ChannelInfo> channel_infos_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChannelManager);
+};
+
+}  // namespace system
+}  // namespace mojo
+
+#endif  // MOJO_EDK_SYSTEM_CHANNEL_MANAGER_H_