WebCore/dom/MessagePort.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/dom/MessagePort.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ *
+ */
+
+#ifndef MessagePort_h
+#define MessagePort_h
+
+#include "AtomicStringHash.h"
+#include "EventListener.h"
+#include "EventTarget.h"
+#include "MessagePortChannel.h"
+#include <wtf/OwnPtr.h>
+#include <wtf/PassOwnPtr.h>
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefPtr.h>
+#include <wtf/Vector.h>
+
+namespace WebCore {
+
+    class AtomicStringImpl;
+    class Event;
+    class Frame;
+    class MessagePort;
+    class ScriptExecutionContext;
+    class String;
+
+    // The overwhelmingly common case is sending a single port, so handle that efficiently with an inline buffer of size 1.
+    typedef Vector<RefPtr<MessagePort>, 1> MessagePortArray;
+
+    class MessagePort : public RefCounted<MessagePort>, public EventTarget {
+    public:
+        static PassRefPtr<MessagePort> create(ScriptExecutionContext& scriptExecutionContext) { return adoptRef(new MessagePort(scriptExecutionContext)); }
+        ~MessagePort();
+
+        void postMessage(PassRefPtr<SerializedScriptValue> message, ExceptionCode&);
+        void postMessage(PassRefPtr<SerializedScriptValue> message, const MessagePortArray*, ExceptionCode&);
+        // FIXME: remove this when we update the ObjC bindings (bug #28774).
+        void postMessage(PassRefPtr<SerializedScriptValue> message, MessagePort*, ExceptionCode&);
+
+        void start();
+        void close();
+
+        void entangle(PassOwnPtr<MessagePortChannel>);
+        PassOwnPtr<MessagePortChannel> disentangle(ExceptionCode&);
+
+        // Disentangle an array of ports, returning the entangled channels.
+        // Per section 8.3.3 of the HTML5 spec, generates an INVALID_STATE_ERR exception if any of the passed ports are null or not entangled.
+        // Returns 0 if there is an exception, or if the passed-in array is 0/empty.
+        static PassOwnPtr<MessagePortChannelArray> disentanglePorts(const MessagePortArray*, ExceptionCode&);
+
+        // Entangles an array of channels, returning an array of MessagePorts in matching order.
+        // Returns 0 if the passed array is 0/empty.
+        static PassOwnPtr<MessagePortArray> entanglePorts(ScriptExecutionContext&, PassOwnPtr<MessagePortChannelArray>);
+
+        void messageAvailable();
+        bool started() const { return m_started; }
+
+        void contextDestroyed();
+
+        virtual ScriptExecutionContext* scriptExecutionContext() const;
+
+        virtual MessagePort* toMessagePort() { return this; }
+
+        void dispatchMessages();
+
+        using RefCounted<MessagePort>::ref;
+        using RefCounted<MessagePort>::deref;
+
+        bool hasPendingActivity();
+
+        void setOnmessage(PassRefPtr<EventListener> listener)
+        {
+            setAttributeEventListener(eventNames().messageEvent, listener);
+            start();
+        }
+        EventListener* onmessage() { return getAttributeEventListener(eventNames().messageEvent); }
+
+        // Returns null if there is no entangled port, or if the entangled port is run by a different thread.
+        // Returns null otherwise.
+        // NOTE: This is used solely to enable a GC optimization. Some platforms may not be able to determine ownership of the remote port (since it may live cross-process) - those platforms may always return null.
+        MessagePort* locallyEntangledPort();
+        // A port starts out its life entangled, and remains entangled until it is closed or is cloned.
+        bool isEntangled() { return !m_closed && !isCloned(); }
+        // A port is cloned if its entangled channel has been removed and sent to a new owner via postMessage().
+        bool isCloned() { return !m_entangledChannel; }
+
+    private:
+        MessagePort(ScriptExecutionContext&);
+
+        virtual void refEventTarget() { ref(); }
+        virtual void derefEventTarget() { deref(); }
+        virtual EventTargetData* eventTargetData();
+        virtual EventTargetData* ensureEventTargetData();
+
+        OwnPtr<MessagePortChannel> m_entangledChannel;
+
+        bool m_started;
+        bool m_closed;
+
+        ScriptExecutionContext* m_scriptExecutionContext;
+        EventTargetData m_eventTargetData;
+    };
+
+} // namespace WebCore
+
+#endif // MessagePort_h