ipc/glue/MessageLink.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: sw=2 ts=4 et :
   3  */
   4 /* This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #ifndef ipc_glue_MessageLink_h
   9 #define ipc_glue_MessageLink_h
  10
  11 #include <cstdint>
  12 #include "base/message_loop.h"
  13 #include "mojo/core/ports/node.h"
  14 #include "mojo/core/ports/port_ref.h"
  15 #include "mozilla/Assertions.h"
  16 #include "mozilla/UniquePtr.h"
  17 #include "mozilla/ipc/ScopedPort.h"
  18
  19 namespace IPC {
  20 class Message;
  21 class MessageReader;
  22 class MessageWriter;
  23 }  // namespace IPC
  24
  25 namespace mozilla {
  26 namespace ipc {
  27
  28 class MessageChannel;
  29 class NodeController;
  30
  31 struct HasResultCodes {
  32   enum Result {
  33     MsgProcessed,
  34     MsgDropped,
  35     MsgNotKnown,
  36     MsgNotAllowed,
  37     MsgPayloadError,
  38     MsgProcessingError,
  39     MsgRouteError,
  40     MsgValueError
  41   };
  42 };
  43
  44 enum Side : uint8_t { ParentSide, ChildSide, UnknownSide };
  45
  46 const char* StringFromIPCSide(Side side);
  47
  48 class MessageLink {
  49  public:
  50   typedef IPC::Message Message;
  51
  52   explicit MessageLink(MessageChannel* aChan);
  53   virtual ~MessageLink();
  54
  55   // n.b.: These methods all require that the channel monitor is
  56   // held when they are invoked.
  57   virtual void SendMessage(mozilla::UniquePtr<Message> msg) = 0;
  58
  59   // Synchronously close the connection, such that no further notifications will
  60   // be delivered to the MessageChannel instance. Must be called with the
  61   // channel monitor held.
  62   virtual void Close() = 0;
  63
  64   virtual bool IsClosed() const = 0;
  65
  66 #ifdef FUZZING_SNAPSHOT
  67   virtual Maybe<mojo::core::ports::PortName> GetPortName() { return Nothing(); }
  68 #endif
  69
  70  protected:
  71   MessageChannel* mChan;
  72 };
  73
  74 class PortLink final : public MessageLink {
  75   using PortRef = mojo::core::ports::PortRef;
  76   using PortStatus = mojo::core::ports::PortStatus;
  77   using UserMessage = mojo::core::ports::UserMessage;
  78   using UserMessageEvent = mojo::core::ports::UserMessageEvent;
  79
  80  public:
  81   PortLink(MessageChannel* aChan, ScopedPort aPort);
  82   virtual ~PortLink();
  83
  84   void SendMessage(UniquePtr<Message> aMessage) override;
  85   void Close() override;
  86
  87   bool IsClosed() const override;
  88
  89 #ifdef FUZZING_SNAPSHOT
  90   Maybe<mojo::core::ports::PortName> GetPortName() override {
  91     return Some(mPort.name());
  92   }
  93 #endif
  94
  95  private:
  96   class PortObserverThunk;
  97   friend class PortObserverThunk;
  98
  99   void OnPortStatusChanged();
 100
 101   // Called either when an error is detected on the port from the port observer,
 102   // or when `SendClose()` is called.
 103   void Clear();
 104
 105   const RefPtr<NodeController> mNode;
 106   const PortRef mPort;
 107
 108   RefPtr<PortObserverThunk> mObserver;
 109 };
 110
 111 }  // namespace ipc
 112 }  // namespace mozilla
 113
 114 #endif  // ifndef ipc_glue_MessageLink_h