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/message_in_transit.h" 19 #include "mojo/system/system_impl_export.h" 20 21 namespace mojo { 22 namespace system { 23 24 class Channel; 25 class Waiter; 26 27 // This is an interface to one of the ends of a message pipe, and is used by 28 // |MessagePipe|. Its most important role is to provide a sink for messages 29 // (i.e., a place where messages can be sent). It has a secondary role: When the 30 // endpoint is local (i.e., in the current process), there'll be a dispatcher 31 // corresponding to the endpoint. In that case, the implementation of 32 // |MessagePipeEndpoint| also implements the functionality required by the 33 // dispatcher, e.g., to read messages and to wait. Implementations of this class 34 // are not thread-safe; instances are protected by |MesssagePipe|'s lock. 35 class MOJO_SYSTEM_IMPL_EXPORT MessagePipeEndpoint { 36 public: 37 virtual ~MessagePipeEndpoint() {} 38 39 enum Type { 40 kTypeLocal, 41 kTypeProxy 42 }; 43 virtual Type GetType() const = 0; 44 45 // All implementations must implement these. 46 // Returns false if the endpoint should be closed and destroyed, else true. 47 virtual bool OnPeerClose() = 0; 48 // Implements |MessagePipe::EnqueueMessage()|. The major differences are that: 49 // a) Dispatchers have been vetted and cloned/attached to the message. 50 // b) At this point, we cannot report failure (if, e.g., a channel is torn 51 // down at this point, we should silently swallow the message). 52 virtual void EnqueueMessage(scoped_ptr<MessageInTransit> message) = 0; 53 54 // Implementations must override these if they represent a local endpoint, 55 // i.e., one for which there's a |MessagePipeDispatcher| (and thus a handle). 56 // An implementation for a proxy endpoint (for which there's no dispatcher) 57 // needs not override these methods, since they should never be called. 58 // 59 // These methods implement the methods of the same name in |MessagePipe|, 60 // though |MessagePipe|'s implementation may have to do a little more if the 61 // operation involves both endpoints. 62 virtual void Close(); 63 virtual void CancelAllWaiters(); 64 virtual MojoResult ReadMessage(void* bytes, 65 uint32_t* num_bytes, 66 DispatcherVector* dispatchers, 67 uint32_t* num_dispatchers, 68 MojoReadMessageFlags flags); 69 virtual MojoResult AddWaiter(Waiter* waiter, 70 MojoHandleSignals signals, 71 uint32_t context); 72 virtual void RemoveWaiter(Waiter* waiter); 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(scoped_refptr<Channel> channel, 78 MessageInTransit::EndpointId local_id); 79 // Returns false if the endpoint should be closed and destroyed, else true. 80 virtual bool Run(MessageInTransit::EndpointId remote_id); 81 virtual void OnRemove(); 82 83 protected: 84 MessagePipeEndpoint() {} 85 86 private: 87 DISALLOW_COPY_AND_ASSIGN(MessagePipeEndpoint); 88 }; 89 90 } // namespace system 91 } // namespace mojo 92 93 #endif // MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_ 94
