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 "bindings/v8/ScriptWrappable.h" 31 #include "core/dom/EventListener.h" 32 #include "core/dom/EventTarget.h" 33 #include "core/dom/MessagePortChannel.h" 34 #include "wtf/Forward.h" 35 #include "wtf/OwnPtr.h" 36 #include "wtf/PassOwnPtr.h" 37 #include "wtf/PassRefPtr.h" 38 #include "wtf/RefPtr.h" 39 #include "wtf/Vector.h" 40 41 namespace WebCore { 42 43 class Event; 44 class ExceptionState; 45 class Frame; 46 class MessagePort; 47 class ScriptExecutionContext; 48 49 // The overwhelmingly common case is sending a single port, so handle that efficiently with an inline buffer of size 1. 50 typedef Vector<RefPtr<MessagePort>, 1> MessagePortArray; 51 52 class MessagePort : public RefCounted<MessagePort>, public ScriptWrappable, public EventTarget { 53 public: 54 static PassRefPtr<MessagePort> create(ScriptExecutionContext& scriptExecutionContext) { return adoptRef(new MessagePort(scriptExecutionContext)); } 55 virtual ~MessagePort(); 56 57 void postMessage(PassRefPtr<SerializedScriptValue> message, const MessagePortArray*, ExceptionState&); 58 59 void start(); 60 void close(); 61 62 void entangle(PassOwnPtr<MessagePortChannel>); 63 PassOwnPtr<MessagePortChannel> disentangle(); 64 65 // Returns 0 if there is an exception, or if the passed-in array is 0/empty. 66 static PassOwnPtr<MessagePortChannelArray> disentanglePorts(const MessagePortArray*, ExceptionState&); 67 68 // Returns 0 if the passed array is 0/empty. 69 static PassOwnPtr<MessagePortArray> entanglePorts(ScriptExecutionContext&, PassOwnPtr<MessagePortChannelArray>); 70 71 void messageAvailable(); 72 bool started() const { return m_started; } 73 74 void contextDestroyed(); 75 76 virtual const AtomicString& interfaceName() const OVERRIDE; 77 virtual ScriptExecutionContext* scriptExecutionContext() const OVERRIDE; 78 79 void dispatchMessages(); 80 81 using RefCounted<MessagePort>::ref; 82 using RefCounted<MessagePort>::deref; 83 84 bool hasPendingActivity(); 85 86 void setOnmessage(PassRefPtr<EventListener> listener, DOMWrapperWorld* world) 87 { 88 setAttributeEventListener(eventNames().messageEvent, listener, world); 89 start(); 90 } 91 EventListener* onmessage(DOMWrapperWorld* world) { return getAttributeEventListener(eventNames().messageEvent, world); } 92 93 // Returns null if there is no entangled port, or if the entangled port is run by a different thread. 94 // This is used solely to enable a GC optimization. Some platforms may not be able to determine ownership 95 // of the remote port (since it may live cross-process) - those platforms may always return null. 96 MessagePort* locallyEntangledPort(); 97 98 // A port starts out its life entangled, and remains entangled until it is closed or is cloned. 99 bool isEntangled() { return !m_closed && !isNeutered(); } 100 101 // A port gets neutered when it is transferred to a new owner via postMessage(). 102 bool isNeutered() { return !m_entangledChannel; } 103 104 private: 105 explicit MessagePort(ScriptExecutionContext&); 106 107 virtual void refEventTarget() OVERRIDE { ref(); } 108 virtual void derefEventTarget() OVERRIDE { deref(); } 109 virtual EventTargetData* eventTargetData() OVERRIDE; 110 virtual EventTargetData* ensureEventTargetData() OVERRIDE; 111 112 OwnPtr<MessagePortChannel> m_entangledChannel; 113 114 bool m_started; 115 bool m_closed; 116 117 ScriptExecutionContext* m_scriptExecutionContext; 118 EventTargetData m_eventTargetData; 119 }; 120 121 } // namespace WebCore 122 123 #endif // MessagePort_h 124