IPC::ChannelMojo: Introduce IPC::MojoBootstrap for Windows

ipc/mojo/ipc_mojo_bootstrap.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 IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
+#define IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "base/process/process_handle.h"
+#include "ipc/ipc_channel.h"
+#include "ipc/ipc_listener.h"
+#include "mojo/embedder/scoped_platform_handle.h"
+
+namespace IPC {
+
+// MojoBootstrap establishes a bootstrap pipe between two processes in
+// Chrome. It creates a native IPC::Channel first, then sends one
+// side of a newly created pipe to peer process. The pipe is intended
+// to be wrapped by Mojo MessagePipe.
+//
+// Clients should implement MojoBootstrapDelegate to get the pipe
+// from MojoBootstrap object. It should also tell the client process handle
+// using OnClientLaunched().
+//
+// This lives on IO thread other than Create(), which can be called from
+// UI thread as Channel::Create() can be.
+class IPC_MOJO_EXPORT MojoBootstrap : public Listener {
+ public:
+  class Delegate {
+   public:
+    virtual void OnPipeAvailable(
+        mojo::embedder::ScopedPlatformHandle handle) = 0;
+    virtual void OnBootstrapError() = 0;
+  };
+
+  // Create the MojoBootstrap instance.
+  // Instead of creating IPC::Channel, passs its ChannelHandle as |handle|,
+  // mode as |mode|. The result is notified to passed |delegate|.
+  static scoped_ptr<MojoBootstrap> Create(ChannelHandle handle,
+                                          Channel::Mode mode,
+                                          Delegate* delegate);
+
+  MojoBootstrap();
+  virtual ~MojoBootstrap();
+
+  // Start the handshake over the underlying platform channel.
+  bool Connect();
+
+  // Each client should call this once the process handle becomes known.
+  virtual void OnClientLaunched(base::ProcessHandle process) = 0;
+
+#if defined(OS_POSIX) && !defined(OS_NACL)
+  int GetClientFileDescriptor() const;
+  int TakeClientFileDescriptor();
+#endif  // defined(OS_POSIX) && !defined(OS_NACL)
+
+ protected:
+  enum State { STATE_INITIALIZED, STATE_WAITING_ACK, STATE_READY };
+
+  Delegate* delegate() const { return delegate_; }
+  bool Send(Message* message);
+
+  State state() const { return state_; }
+  void set_state(State state) { state_ = state; }
+
+ private:
+  void Init(scoped_ptr<Channel> channel, Delegate* delegate);
+
+  // Listener implementations
+  virtual void OnBadMessageReceived(const Message& message) OVERRIDE;
+  virtual void OnChannelError() OVERRIDE;
+
+  scoped_ptr<Channel> channel_;
+  Delegate* delegate_;
+  State state_;
+
+  DISALLOW_COPY_AND_ASSIGN(MojoBootstrap);
+};
+
+}  // namespace IPC
+
+#endif  // IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_