ipc/mojo/ipc_mojo_bootstrap.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
   6 #define IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "base/process/process_handle.h"
  10 #include "ipc/ipc_channel.h"
  11 #include "ipc/ipc_listener.h"
  12 #include "third_party/mojo/src/mojo/edk/embedder/scoped_platform_handle.h"
  13
  14 namespace IPC {
  15
  16 class AttachmentBroker;
  17
  18 // MojoBootstrap establishes a bootstrap pipe between two processes in
  19 // Chrome. It creates a native IPC::Channel first, then sends one
  20 // side of a newly created pipe to peer process. The pipe is intended
  21 // to be wrapped by Mojo MessagePipe.
  22 //
  23 // Clients should implement MojoBootstrapDelegate to get the pipe
  24 // from MojoBootstrap object. It should also tell the client process handle
  25 // using OnClientLaunched().
  26 //
  27 // This lives on IO thread other than Create(), which can be called from
  28 // UI thread as Channel::Create() can be.
  29 class IPC_MOJO_EXPORT MojoBootstrap : public Listener {
  30  public:
  31   class Delegate {
  32    public:
  33     virtual void OnPipeAvailable(
  34         mojo::embedder::ScopedPlatformHandle handle) = 0;
  35     virtual void OnBootstrapError() = 0;
  36   };
  37
  38   // Create the MojoBootstrap instance.
  39   // Instead of creating IPC::Channel, passs its ChannelHandle as |handle|,
  40   // mode as |mode|. The result is notified to passed |delegate|.
  41   static scoped_ptr<MojoBootstrap> Create(ChannelHandle handle,
  42                                           Channel::Mode mode,
  43                                           Delegate* delegate,
  44                                           AttachmentBroker* broker);
  45
  46   MojoBootstrap();
  47   ~MojoBootstrap() override;
  48
  49   // Start the handshake over the underlying platform channel.
  50   bool Connect();
  51
  52   // GetSelfPID returns the PID associated with |channel_|.
  53   base::ProcessId GetSelfPID() const;
  54
  55   // Each client should call this once the process handle becomes known.
  56   virtual void OnClientLaunched(base::ProcessHandle process) = 0;
  57
  58 #if defined(OS_POSIX) && !defined(OS_NACL)
  59   int GetClientFileDescriptor() const;
  60   base::ScopedFD TakeClientFileDescriptor();
  61 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
  62
  63  protected:
  64   // On MojoServerBootstrap: INITIALIZED -> WAITING_ACK -> READY
  65   // On MojoClientBootstrap: INITIALIZED -> READY
  66   // STATE_ERROR is a catch-all state that captures any observed error.
  67   enum State { STATE_INITIALIZED, STATE_WAITING_ACK, STATE_READY, STATE_ERROR };
  68
  69   Delegate* delegate() const { return delegate_; }
  70   bool Send(Message* message);
  71   void Fail();
  72   bool HasFailed() const;
  73
  74   State state() const { return state_; }
  75   void set_state(State state) { state_ = state; }
  76
  77  private:
  78   void Init(scoped_ptr<Channel> channel, Delegate* delegate);
  79
  80   // Listener implementations
  81   void OnBadMessageReceived(const Message& message) override;
  82   void OnChannelError() override;
  83
  84   scoped_ptr<Channel> channel_;
  85   Delegate* delegate_;
  86   State state_;
  87
  88   DISALLOW_COPY_AND_ASSIGN(MojoBootstrap);
  89 };
  90
  91 }  // namespace IPC
  92
  93 #endif  // IPC_MOJO_IPC_MOJO_BOOTSTRAP_H_