WebCore/MessagePort.h

   1 /*
   2  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  *
  25  */
  26
  27 #ifndef MessagePort_h
  28 #define MessagePort_h
  29
  30 #include "AtomicStringHash.h"
  31 #include "EventListener.h"
  32 #include "EventTarget.h"
  33
  34 #include <wtf/HashMap.h>
  35 #include <wtf/MessageQueue.h>
  36 #include <wtf/PassRefPtr.h>
  37 #include <wtf/RefPtr.h>
  38 #include <wtf/Vector.h>
  39
  40 namespace WebCore {
  41
  42     class AtomicStringImpl;
  43     class Event;
  44     class Frame;
  45     class ScriptExecutionContext;
  46     class String;
  47     class WorkerContext;
  48
  49     class MessagePort : public RefCounted<MessagePort>, public EventTarget {
  50     public:
  51         static PassRefPtr<MessagePort> create(ScriptExecutionContext* scriptExecutionContext) { return adoptRef(new MessagePort(scriptExecutionContext)); }
  52         ~MessagePort();
  53
  54         PassRefPtr<MessagePort> clone(ExceptionCode&); // Returns a port that isn't attached to any context.
  55
  56         bool active() const { return m_entangledPort; }
  57         void postMessage(const String& message, ExceptionCode&);
  58         void postMessage(const String& message, MessagePort*, ExceptionCode&);
  59         PassRefPtr<MessagePort> startConversation(ScriptExecutionContext*, const String& message);
  60         void start();
  61         void close();
  62
  63         bool queueIsOpen() const { return m_queueIsOpen; }
  64
  65         MessagePort* entangledPort() { return m_entangledPort; }
  66         static void entangle(MessagePort*, MessagePort*);
  67         void unentangle();
  68
  69         void contextDestroyed();
  70         void attachToContext(ScriptExecutionContext*);
  71         virtual ScriptExecutionContext* scriptExecutionContext() const;
  72
  73         virtual MessagePort* toMessagePort() { return this; }
  74
  75         void queueCloseEvent();
  76         void dispatchMessages();
  77
  78         virtual void addEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture);
  79         virtual void removeEventListener(const AtomicString& eventType, EventListener*, bool useCapture);
  80         virtual bool dispatchEvent(PassRefPtr<Event>, ExceptionCode&);
  81
  82         typedef Vector<RefPtr<EventListener> > ListenerVector;
  83         typedef HashMap<AtomicString, ListenerVector> EventListenersMap;
  84         EventListenersMap& eventListeners() { return m_eventListeners; }
  85
  86         using RefCounted<MessagePort>::ref;
  87         using RefCounted<MessagePort>::deref;
  88
  89         bool hasPendingActivity();
  90
  91         // FIXME: Per current spec, setting onmessage should automagically start the port (unlike addEventListener("message", ...)).
  92         void setOnmessage(PassRefPtr<EventListener> eventListener) { m_onMessageListener = eventListener; }
  93         EventListener* onmessage() const { return m_onMessageListener.get(); }
  94
  95         void setOnclose(PassRefPtr<EventListener> eventListener) { m_onCloseListener = eventListener; }
  96         EventListener* onclose() const { return m_onCloseListener.get(); }
  97
  98     private:
  99         friend class MessagePortCloseEventTask;
 100
 101         MessagePort(ScriptExecutionContext*);
 102
 103         virtual void refEventTarget() { ref(); }
 104         virtual void derefEventTarget() { deref(); }
 105
 106         void dispatchCloseEvent();
 107
 108         MessagePort* m_entangledPort;
 109
 110         // FIXME: EventData is necessary to pass messages to other threads. In single threaded case, we can just queue a created event.
 111         struct EventData : public RefCounted<EventData> {
 112             static PassRefPtr<EventData> create(const String& message, PassRefPtr<MessagePort>);
 113             ~EventData();
 114
 115             String message;
 116             RefPtr<MessagePort> messagePort;
 117
 118         private:
 119             EventData(const String& message, PassRefPtr<MessagePort>);
 120         };
 121         MessageQueue<RefPtr<EventData> > m_messageQueue; // FIXME: No need to use MessageQueue in single threaded case.
 122         bool m_queueIsOpen;
 123
 124         ScriptExecutionContext* m_scriptExecutionContext;
 125
 126         RefPtr<EventListener> m_onMessageListener;
 127         RefPtr<EventListener> m_onCloseListener;
 128
 129         EventListenersMap m_eventListeners;
 130
 131         bool m_pendingCloseEvent; // The port is GC protected while waiting for a close event to be dispatched.
 132     };
 133
 134 } // namespace WebCore
 135
 136 #endif // MessagePort_h