blob: 7da65f07a26c06829c32330005e75c5fd153afae [file] [log] [blame]
// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_
#define MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_
#include <stdint.h>
#include <vector>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "mojo/public/c/system/message_pipe.h"
#include "mojo/public/c/system/types.h"
#include "mojo/system/dispatcher.h"
#include "mojo/system/message_in_transit.h"
#include "mojo/system/system_impl_export.h"
namespace mojo {
namespace system {
class Channel;
class Waiter;
// This is an interface to one of the ends of a message pipe, and is used by
// |MessagePipe|. Its most important role is to provide a sink for messages
// (i.e., a place where messages can be sent). It has a secondary role: When the
// endpoint is local (i.e., in the current process), there'll be a dispatcher
// corresponding to the endpoint. In that case, the implementation of
// |MessagePipeEndpoint| also implements the functionality required by the
// dispatcher, e.g., to read messages and to wait. Implementations of this class
// are not thread-safe; instances are protected by |MesssagePipe|'s lock.
class MOJO_SYSTEM_IMPL_EXPORT MessagePipeEndpoint {
public:
virtual ~MessagePipeEndpoint() {}
enum Type {
kTypeLocal,
kTypeProxy
};
virtual Type GetType() const = 0;
// All implementations must implement these.
// Returns false if the endpoint should be closed and destroyed, else true.
virtual bool OnPeerClose() = 0;
// Implements |MessagePipe::EnqueueMessage()|. The major differences are that:
// a) Dispatchers have been vetted and cloned/attached to the message.
// b) At this point, we cannot report failure (if, e.g., a channel is torn
// down at this point, we should silently swallow the message).
virtual void EnqueueMessage(scoped_ptr<MessageInTransit> message) = 0;
// Implementations must override these if they represent a local endpoint,
// i.e., one for which there's a |MessagePipeDispatcher| (and thus a handle).
// An implementation for a proxy endpoint (for which there's no dispatcher)
// needs not override these methods, since they should never be called.
//
// These methods implement the methods of the same name in |MessagePipe|,
// though |MessagePipe|'s implementation may have to do a little more if the
// operation involves both endpoints.
virtual void Close();
virtual void CancelAllWaiters();
virtual MojoResult ReadMessage(void* bytes,
uint32_t* num_bytes,
DispatcherVector* dispatchers,
uint32_t* num_dispatchers,
MojoReadMessageFlags flags);
virtual MojoResult AddWaiter(Waiter* waiter,
MojoHandleSignals signals,
uint32_t context);
virtual void RemoveWaiter(Waiter* waiter);
// Implementations must override these if they represent a proxy endpoint. An
// implementation for a local endpoint needs not override these methods, since
// they should never be called.
virtual void Attach(scoped_refptr<Channel> channel,
MessageInTransit::EndpointId local_id);
// Returns false if the endpoint should be closed and destroyed, else true.
virtual bool Run(MessageInTransit::EndpointId remote_id);
virtual void OnRemove();
protected:
MessagePipeEndpoint() {}
private:
DISALLOW_COPY_AND_ASSIGN(MessagePipeEndpoint);
};
} // namespace system
} // namespace mojo
#endif // MOJO_SYSTEM_MESSAGE_PIPE_ENDPOINT_H_