ipc/mojo/ipc_channel_mojo.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_IPC_CHANNEL_MOJO_H_
   6 #define IPC_IPC_CHANNEL_MOJO_H_
   7
   8 #include <vector>
   9
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/memory/scoped_vector.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "ipc/ipc_channel.h"
  14 #include "ipc/ipc_channel_factory.h"
  15 #include "ipc/ipc_export.h"
  16 #include "ipc/mojo/ipc_message_pipe_reader.h"
  17 #include "ipc/mojo/ipc_mojo_bootstrap.h"
  18 #include "ipc/mojo/scoped_ipc_support.h"
  19 #include "third_party/mojo/src/mojo/edk/embedder/channel_info_forward.h"
  20 #include "third_party/mojo/src/mojo/public/cpp/system/core.h"
  21
  22 namespace IPC {
  23
  24 // Mojo-based IPC::Channel implementation over a platform handle.
  25 //
  26 // ChannelMojo builds Mojo MessagePipe using underlying pipe given by
  27 // "bootstrap" IPC::Channel which creates and owns platform pipe like
  28 // named socket. The bootstrap Channel is used only for establishing
  29 // the underlying connection. ChannelMojo takes its handle over once
  30 // the it is made and puts MessagePipe on it.
  31 //
  32 // ChannelMojo has a couple of MessagePipes:
  33 //
  34 // * The first MessagePipe, which is built on top of bootstrap handle,
  35 //   is the "control" pipe. It is used to communicate out-of-band
  36 //   control messages that aren't visible from IPC::Listener.
  37 //
  38 // * The second MessagePipe, which is created by the server channel
  39 //   and sent to client Channel over the control pipe, is used
  40 //   to send IPC::Messages as an IPC::Sender.
  41 //
  42 // TODO(morrita): Extract handle creation part of IPC::Channel into
  43 //                separate class to clarify what ChannelMojo relies
  44 //                on.
  45 // TODO(morrita): Add APIs to create extra MessagePipes to let
  46 //                Mojo-based objects talk over this Channel.
  47 //
  48 class IPC_MOJO_EXPORT ChannelMojo
  49     : public Channel,
  50       public MojoBootstrap::Delegate,
  51       public NON_EXPORTED_BASE(internal::MessagePipeReader::Delegate) {
  52  public:
  53   class Delegate {
  54    public:
  55     virtual ~Delegate() {}
  56     virtual base::WeakPtr<Delegate> ToWeakPtr() = 0;
  57     virtual scoped_refptr<base::TaskRunner> GetIOTaskRunner() = 0;
  58     virtual void OnChannelCreated(base::WeakPtr<ChannelMojo> channel) = 0;
  59   };
  60
  61   // True if ChannelMojo should be used regardless of the flag.
  62   static bool ShouldBeUsed();
  63
  64   // Create ChannelMojo. A bootstrap channel is created as well.
  65   // |host| must not be null for server channels.
  66   static scoped_ptr<ChannelMojo> Create(Delegate* delegate,
  67                                         const ChannelHandle& channel_handle,
  68                                         Mode mode,
  69                                         Listener* listener);
  70
  71   // Create a factory object for ChannelMojo.
  72   // The factory is used to create Mojo-based ChannelProxy family.
  73   // |host| must not be null.
  74   static scoped_ptr<ChannelFactory> CreateServerFactory(
  75       Delegate* delegate,
  76       const ChannelHandle& channel_handle);
  77
  78   static scoped_ptr<ChannelFactory> CreateClientFactory(
  79       Delegate* delegate,
  80       const ChannelHandle& channel_handle);
  81
  82   ~ChannelMojo() override;
  83
  84   // ChannelMojoHost tells the client handle using this API.
  85   void OnClientLaunched(base::ProcessHandle handle);
  86
  87   // Channel implementation
  88   bool Connect() override;
  89   void Close() override;
  90   bool Send(Message* message) override;
  91   base::ProcessId GetPeerPID() const override;
  92   base::ProcessId GetSelfPID() const override;
  93
  94 #if defined(OS_POSIX) && !defined(OS_NACL)
  95   int GetClientFileDescriptor() const override;
  96   base::ScopedFD TakeClientFileDescriptor() override;
  97 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
  98
  99   // These access protected API of IPC::Message, which has ChannelMojo
 100   // as a friend class.
 101   static MojoResult WriteToMessageAttachmentSet(
 102       const std::vector<MojoHandle>& handle_buffer,
 103       Message* message);
 104   static MojoResult ReadFromMessageAttachmentSet(
 105       Message* message,
 106       std::vector<MojoHandle>* handles);
 107
 108   // MojoBootstrapDelegate implementation
 109   void OnBootstrapError() override;
 110
 111   // MessagePipeReader::Delegate
 112   void OnMessageReceived(Message& message) override;
 113   void OnPipeClosed(internal::MessagePipeReader* reader) override;
 114   void OnPipeError(internal::MessagePipeReader* reader) override;
 115
 116  protected:
 117   ChannelMojo(Delegate* delegate,
 118               const ChannelHandle& channel_handle,
 119               Mode mode,
 120               Listener* listener);
 121
 122   mojo::ScopedMessagePipeHandle CreateMessagingPipe(
 123       mojo::embedder::ScopedPlatformHandle handle);
 124   void InitMessageReader(mojo::ScopedMessagePipeHandle pipe, int32_t peer_pid);
 125
 126   Listener* listener() const { return listener_; }
 127   void set_peer_pid(base::ProcessId pid) { peer_pid_ = pid; }
 128
 129  private:
 130   struct ChannelInfoDeleter {
 131     void operator()(mojo::embedder::ChannelInfo* ptr) const;
 132   };
 133
 134   // ChannelMojo needs to kill its MessagePipeReader in delayed manner
 135   // because the channel wants to kill these readers during the
 136   // notifications invoked by them.
 137   typedef internal::MessagePipeReader::DelayedDeleter ReaderDeleter;
 138
 139   void InitDelegate(ChannelMojo::Delegate* delegate);
 140
 141   scoped_ptr<MojoBootstrap> bootstrap_;
 142   base::WeakPtr<Delegate> delegate_;
 143   Mode mode_;
 144   Listener* listener_;
 145   base::ProcessId peer_pid_;
 146   scoped_ptr<mojo::embedder::ChannelInfo,
 147              ChannelInfoDeleter> channel_info_;
 148
 149   scoped_ptr<internal::MessagePipeReader, ReaderDeleter> message_reader_;
 150   ScopedVector<Message> pending_messages_;
 151
 152   scoped_ptr<ScopedIPCSupport> ipc_support_;
 153
 154   base::WeakPtrFactory<ChannelMojo> weak_factory_;
 155
 156   DISALLOW_COPY_AND_ASSIGN(ChannelMojo);
 157 };
 158
 159 }  // namespace IPC
 160
 161 #endif  // IPC_IPC_CHANNEL_MOJO_H_