[mojo] Ports EDK

mojo/edk/system/node_channel.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_NODE_CHANNEL_H_
+#define MOJO_EDK_SYSTEM_NODE_CHANNEL_H_
+
+#include <unordered_map>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/process/process_handle.h"
+#include "base/synchronization/lock.h"
+#include "base/task_runner.h"
+#include "build/build_config.h"
+#include "mojo/edk/embedder/platform_handle_vector.h"
+#include "mojo/edk/embedder/scoped_platform_handle.h"
+#include "mojo/edk/system/channel.h"
+#include "mojo/edk/system/ports/name.h"
+
+namespace mojo {
+namespace edk {
+
+// Wraps a Channel to send and receive Node control messages.
+class NodeChannel : public base::RefCountedThreadSafe<NodeChannel>,
+                    public Channel::Delegate {
+ public:
+  class Delegate {
+   public:
+    virtual ~Delegate() {}
+    virtual void OnAcceptChild(const ports::NodeName& from_node,
+                               const ports::NodeName& parent_name,
+                               const ports::NodeName& token) = 0;
+    virtual void OnAcceptParent(const ports::NodeName& from_node,
+                                const ports::NodeName& token,
+                                const ports::NodeName& child_name) = 0;
+    virtual void OnPortsMessage(Channel::MessagePtr message) = 0;
+    virtual void OnRequestPortConnection(
+        const ports::NodeName& from_node,
+        const ports::PortName& connector_port_name,
+        const std::string& token) = 0;
+    virtual void OnConnectToPort(
+        const ports::NodeName& from_node,
+        const ports::PortName& connector_port_name,
+        const ports::PortName& connectee_port_name) = 0;
+    virtual void OnRequestIntroduction(const ports::NodeName& from_node,
+                                       const ports::NodeName& name) = 0;
+    virtual void OnIntroduce(const ports::NodeName& from_node,
+                             const ports::NodeName& name,
+                             ScopedPlatformHandle channel_handle) = 0;
+#if defined(OS_WIN)
+    virtual void OnRelayPortsMessage(const ports::NodeName& from_node,
+                                     base::ProcessHandle from_process,
+                                     const ports::NodeName& destination,
+                                     Channel::MessagePtr message) = 0;
+#endif
+
+    virtual void OnChannelError(const ports::NodeName& node) = 0;
+  };
+
+  static scoped_refptr<NodeChannel> Create(
+      Delegate* delegate,
+      ScopedPlatformHandle platform_handle,
+      scoped_refptr<base::TaskRunner> io_task_runner);
+
+  static Channel::MessagePtr CreatePortsMessage(size_t payload_size,
+                                                void** payload,
+                                                size_t num_handles);
+
+  static void GetPortsMessageData(Channel::Message* message, void** data,
+                                  size_t* num_data_bytes);
+
+  // Start receiving messages.
+  void Start();
+
+  // Permanently stop the channel from sending or receiving messages.
+  void ShutDown();
+
+  void SetRemoteProcessHandle(base::ProcessHandle process_handle);
+
+  // Used for context in Delegate calls (via |from_node| arguments.)
+  void SetRemoteNodeName(const ports::NodeName& name);
+
+  void AcceptChild(const ports::NodeName& parent_name,
+                   const ports::NodeName& token);
+  void AcceptParent(const ports::NodeName& token,
+                    const ports::NodeName& child_name);
+  void PortsMessage(Channel::MessagePtr message);
+  void RequestPortConnection(const ports::PortName& connector_port_name,
+                             const std::string& token);
+  void ConnectToPort(const ports::PortName& connector_port_name,
+                     const ports::PortName& connectee_port_name);
+  void RequestIntroduction(const ports::NodeName& name);
+  void Introduce(const ports::NodeName& name, ScopedPlatformHandle handle);
+
+#if defined(OS_WIN)
+  // Relay the message to the specified node via this channel.  This is used to
+  // pass windows handles between two processes that do not have permission to
+  // duplicate handles into the other's address space. The relay process is
+  // assumed to have that permission.
+  void RelayPortsMessage(const ports::NodeName& destination,
+                         Channel::MessagePtr message);
+#endif
+
+ private:
+  friend class base::RefCountedThreadSafe<NodeChannel>;
+
+  NodeChannel(Delegate* delegate,
+              ScopedPlatformHandle platform_handle,
+              scoped_refptr<base::TaskRunner> io_task_runner);
+  ~NodeChannel() override;
+
+  // Channel::Delegate:
+  void OnChannelMessage(const void* payload,
+                        size_t payload_size,
+                        ScopedPlatformHandleVectorPtr handles) override;
+  void OnChannelError() override;
+
+  void WriteChannelMessage(Channel::MessagePtr message);
+
+  Delegate* const delegate_;
+  const scoped_refptr<base::TaskRunner> io_task_runner_;
+
+  base::Lock channel_lock_;
+  scoped_refptr<Channel> channel_;
+
+  // Must only be accessed from |io_task_runner_|'s thread.
+  ports::NodeName remote_node_name_;
+
+#if defined(OS_WIN)
+  base::Lock remote_process_handle_lock_;
+  base::ProcessHandle remote_process_handle_ = base::kNullProcessHandle;
+#endif
+
+  DISALLOW_COPY_AND_ASSIGN(NodeChannel);
+};
+
+}  // namespace edk
+}  // namespace mojo
+
+#endif  // MOJO_EDK_SYSTEM_NODE_CHANNEL_H_