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31 #ifndef MessagePortChannel_h
32 #define MessagePortChannel_h
34 #include "PlatformString.h"
36 #include "SerializedScriptValue.h"
38 #include <wtf/OwnPtr.h>
39 #include <wtf/Forward.h>
40 #include <wtf/PassOwnPtr.h>
41 #include <wtf/PassRefPtr.h>
42 #include <wtf/RefCounted.h>
43 #include <wtf/RefPtr.h>
48 class MessagePortChannel;
49 class PlatformMessagePortChannel;
50 class ScriptExecutionContext;
51 class SerializedScriptValue;
53 // The overwhelmingly common case is sending a single port, so handle that efficiently with an inline buffer of size 1.
54 typedef Vector<OwnPtr<MessagePortChannel>, 1> MessagePortChannelArray;
56 // MessagePortChannel is a platform-independent interface to the remote side of a message channel.
57 // It acts as a wrapper around the platform-dependent PlatformMessagePortChannel implementation which ensures that the platform-dependent close() method is invoked before destruction.
58 class MessagePortChannel {
59 WTF_MAKE_NONCOPYABLE(MessagePortChannel); WTF_MAKE_FAST_ALLOCATED;
61 static void createChannel(PassRefPtr<MessagePort>, PassRefPtr<MessagePort>);
63 // Creates a new wrapper for the passed channel.
64 static PassOwnPtr<MessagePortChannel> create(PassRefPtr<PlatformMessagePortChannel>);
66 // Entangles the channel with a port (called when a port has been cloned, after the clone has been marshaled to its new owning thread and is ready to receive messages).
67 // Returns false if the entanglement failed because the port was closed.
68 bool entangleIfOpen(MessagePort*);
70 // Disentangles the channel from a given port so it no longer forwards messages to the port. Called when the port is being cloned and no new owning thread has yet been established.
73 // Closes the port (ensures that no further messages can be added to either queue).
76 // Used by MessagePort.postMessage() to prevent callers from passing a port's own entangled port.
77 bool isConnectedTo(MessagePort*);
79 // Returns true if the proxy currently contains messages for this port.
80 bool hasPendingActivity();
83 WTF_MAKE_NONCOPYABLE(EventData); WTF_MAKE_FAST_ALLOCATED;
85 static PassOwnPtr<EventData> create(PassRefPtr<SerializedScriptValue>, PassOwnPtr<MessagePortChannelArray>);
87 SerializedScriptValue* message() { return m_message.get(); }
88 PassOwnPtr<MessagePortChannelArray> channels() { return m_channels.release(); }
91 EventData(PassRefPtr<SerializedScriptValue> message, PassOwnPtr<MessagePortChannelArray>);
92 RefPtr<SerializedScriptValue> m_message;
93 OwnPtr<MessagePortChannelArray> m_channels;
96 // Sends a message and optional cloned port to the remote port.
97 void postMessageToRemote(PassOwnPtr<EventData>);
99 // Extracts a message from the message queue for this port.
100 bool tryGetMessageFromRemote(OwnPtr<EventData>&);
102 // Returns the entangled port if run by the same thread (see MessagePort::locallyEntangledPort() for more details).
103 MessagePort* locallyEntangledPort(const ScriptExecutionContext*);
105 ~MessagePortChannel();
107 PlatformMessagePortChannel* channel() const { return m_channel.get(); }
110 MessagePortChannel(PassRefPtr<PlatformMessagePortChannel>);
111 RefPtr<PlatformMessagePortChannel> m_channel;
114 } // namespace WebCore
116 #endif // MessagePortChannel_h