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31 #ifndef PlatformMessagePortChannel_h
32 #define PlatformMessagePortChannel_h
34 #include "MessagePortChannel.h"
36 #include <wtf/MessageQueue.h>
37 #include <wtf/PassRefPtr.h>
38 #include <wtf/Threading.h>
44 // PlatformMessagePortChannel is a platform-dependent interface to the remote side of a message channel.
45 // This default implementation supports multiple threads running within a single process. Implementations for multi-process platforms should define these public APIs in their own platform-specific PlatformMessagePortChannel file.
46 // The goal of this implementation is to eliminate contention except when cloning or closing the port, so each side of the channel has its own separate mutex.
47 class PlatformMessagePortChannel : public ThreadSafeRefCounted<PlatformMessagePortChannel> {
49 static void createChannel(PassRefPtr<MessagePort>, PassRefPtr<MessagePort>);
51 // APIs delegated from MessagePortChannel.h
52 bool entangleIfOpen(MessagePort*);
54 void postMessageToRemote(PassOwnPtr<MessagePortChannel::EventData>);
55 bool tryGetMessageFromRemote(OwnPtr<MessagePortChannel::EventData>&);
57 bool isConnectedTo(MessagePort*);
58 bool hasPendingActivity();
59 MessagePort* locallyEntangledPort(const ScriptExecutionContext*);
61 // Wrapper for MessageQueue that allows us to do thread safe sharing by two proxies.
62 class MessagePortQueue : public ThreadSafeRefCounted<MessagePortQueue> {
64 static PassRefPtr<MessagePortQueue> create() { return adoptRef(new MessagePortQueue()); }
66 PassOwnPtr<MessagePortChannel::EventData> tryGetMessage()
68 return m_queue.tryGetMessage();
71 bool appendAndCheckEmpty(PassOwnPtr<MessagePortChannel::EventData> message)
73 return m_queue.appendAndCheckEmpty(message);
78 return m_queue.isEmpty();
82 MessagePortQueue() { }
84 MessageQueue<MessagePortChannel::EventData> m_queue;
87 ~PlatformMessagePortChannel();
90 static PassRefPtr<PlatformMessagePortChannel> create(PassRefPtr<MessagePortQueue> incoming, PassRefPtr<MessagePortQueue> outgoing);
91 PlatformMessagePortChannel(PassRefPtr<MessagePortQueue> incoming, PassRefPtr<MessagePortQueue> outgoing);
93 PassRefPtr<PlatformMessagePortChannel> entangledChannel();
94 void setEntangledChannel(PassRefPtr<PlatformMessagePortChannel>);
96 void setRemotePort(MessagePort*);
97 MessagePort* remotePort();
100 // Mutex used to ensure exclusive access to the object internals.
103 // Pointer to our entangled pair - cleared when close() is called.
104 RefPtr<PlatformMessagePortChannel> m_entangledChannel;
106 // Reference to the message queue for the (local) entangled port.
107 RefPtr<MessagePortQueue> m_incomingQueue;
108 RefPtr<MessagePortQueue> m_outgoingQueue;
110 // The port we are connected to (the remote port) - this is the port that is notified when new messages arrive.
111 MessagePort* m_remotePort;
114 } // namespace WebCore
116 #endif // PlatformMessagePortChannel_h