1 // Copyright 2013 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 MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_ 6 #define MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_ 7 8 #include <stdint.h> 9 10 #include <vector> 11 12 #include "base/macros.h" 13 #include "base/memory/ref_counted.h" 14 #include "base/memory/scoped_ptr.h" 15 #include "mojo/public/c/system/message_pipe.h" 16 #include "mojo/public/c/system/types.h" 17 #include "mojo/system/dispatcher.h" 18 #include "mojo/system/memory.h" 19 #include "mojo/system/message_in_transit.h" 20 #include "mojo/system/system_impl_export.h" 21 22 namespace mojo { 23 namespace system { 24 25 class ChannelEndpoint; 26 class Waiter; 27 28 // This is an interface to one of the ends of a message pipe, and is used by 29 // |MessagePipe|. Its most important role is to provide a sink for messages 30 // (i.e., a place where messages can be sent). It has a secondary role: When the 31 // endpoint is local (i.e., in the current process), there'll be a dispatcher 32 // corresponding to the endpoint. In that case, the implementation of 33 // |MessagePipeEndpoint| also implements the functionality required by the 34 // dispatcher, e.g., to read messages and to wait. Implementations of this class 35 // are not thread-safe; instances are protected by |MesssagePipe|'s lock. 36 class MOJO_SYSTEM_IMPL_EXPORT MessagePipeEndpoint { 37 public: 38 virtual ~MessagePipeEndpoint() {} 39 40 enum Type { kTypeLocal, kTypeProxy }; 41 virtual Type GetType() const = 0; 42 43 // All implementations must implement these. 44 // Returns false if the endpoint should be closed and destroyed, else true. 45 virtual bool OnPeerClose() = 0; 46 // Implements |MessagePipe::EnqueueMessage()|. The major differences are that: 47 // a) Dispatchers have been vetted and cloned/attached to the message. 48 // b) At this point, we cannot report failure (if, e.g., a channel is torn 49 // down at this point, we should silently swallow the message). 50 virtual void EnqueueMessage(scoped_ptr<MessageInTransit> message) = 0; 51 52 // Implementations must override these if they represent a local endpoint, 53 // i.e., one for which there's a |MessagePipeDispatcher| (and thus a handle). 54 // An implementation for a proxy endpoint (for which there's no dispatcher) 55 // needs not override these methods, since they should never be called. 56 // 57 // These methods implement the methods of the same name in |MessagePipe|, 58 // though |MessagePipe|'s implementation may have to do a little more if the 59 // operation involves both endpoints. 60 virtual void Close(); 61 virtual void CancelAllWaiters(); 62 virtual MojoResult ReadMessage(UserPointer<void> bytes, 63 UserPointer<uint32_t> num_bytes, 64 DispatcherVector* dispatchers, 65 uint32_t* num_dispatchers, 66 MojoReadMessageFlags flags); 67 virtual HandleSignalsState GetHandleSignalsState() const; 68 virtual MojoResult AddWaiter(Waiter* waiter, 69 MojoHandleSignals signals, 70 uint32_t context, 71 HandleSignalsState* signals_state); 72 virtual void RemoveWaiter(Waiter* waiter, HandleSignalsState* signals_state); 73 74 // Implementations must override these if they represent a proxy endpoint. An 75 // implementation for a local endpoint needs not override these methods, since 76 // they should never be called. 77 virtual void Attach(ChannelEndpoint* channel_endpoint); 78 79 protected: 80 MessagePipeEndpoint() {} 81 82 private: 83 DISALLOW_COPY_AND_ASSIGN(MessagePipeEndpoint); 84 }; 85 86 } // namespace system 87 } // namespace mojo 88 89 #endif // MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_ 90
