Source/core/dom/MessagePortChannel.cpp

/*
 * Copyright (C) 2009 Google Inc. All rights reserved.
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#include "config.h"
#include "core/dom/MessagePortChannel.h"

#include "core/dom/MessagePort.h"
#include "public/platform/Platform.h"
#include "public/platform/WebMessagePortChannel.h"
#include "public/platform/WebString.h"
#include "wtf/PassRefPtr.h"

namespace WebCore {

PassRefPtr<MessagePortChannel> MessagePortChannel::create(WebKit::WebMessagePortChannel* channel)
{
    return adoptRef(new MessagePortChannel(channel));
}

void MessagePortChannel::createChannel(MessagePort* port1, MessagePort* port2)
{
    // Create proxies for each endpoint.
    RefPtr<MessagePortChannel> channel1 = create(WebKit::Platform::current()->createMessagePortChannel());
    RefPtr<MessagePortChannel> channel2 = create(WebKit::Platform::current()->createMessagePortChannel());

    // Entangle the two endpoints.
    channel1->setEntangledChannel(channel2);
    channel2->setEntangledChannel(channel1);

    // Now entangle the proxies with the appropriate local ports.
    port1->entangle(channel2.release());
    port2->entangle(channel1.release());
}

MessagePortChannel::MessagePortChannel(WebKit::WebMessagePortChannel* channel)
    : m_localPort(0)
    , m_webChannel(channel)
{
    ASSERT(m_webChannel);
    m_webChannel->setClient(this);
}

MessagePortChannel::~MessagePortChannel()
{
    if (m_webChannel)
        m_webChannel->destroy();
}

void MessagePortChannel::entangle(MessagePort* port)
{
    MutexLocker lock(m_mutex);
    m_localPort = port;
}

void MessagePortChannel::disentangle()
{
    MutexLocker lock(m_mutex);
    m_localPort = 0;
}

void MessagePortChannel::postMessageToRemote(PassRefPtr<SerializedScriptValue> message, PassOwnPtr<MessagePortChannelArray> channels)
{
    if (!m_localPort || !m_webChannel)
        return;

    WebKit::WebString messageString = message->toWireString();
    WebKit::WebMessagePortChannelArray* webChannels = 0;
    if (channels && channels->size()) {
        webChannels = new WebKit::WebMessagePortChannelArray(channels->size());
        for (size_t i = 0; i < channels->size(); ++i)
            (*webChannels)[i] = (*channels)[i]->webChannelRelease();
    }
    m_webChannel->postMessage(messageString, webChannels);
}

bool MessagePortChannel::tryGetMessageFromRemote(RefPtr<SerializedScriptValue>& serializedMessage, OwnPtr<MessagePortChannelArray>& channels)
{
    if (!m_webChannel)
        return false;

    WebKit::WebString message;
    WebKit::WebMessagePortChannelArray webChannels;
    bool rv = m_webChannel->tryGetMessage(&message, webChannels);
    if (rv) {
        if (webChannels.size()) {
            channels = adoptPtr(new MessagePortChannelArray(webChannels.size()));
            for (size_t i = 0; i < webChannels.size(); ++i)
                (*channels)[i] = MessagePortChannel::create(webChannels[i]);
        }
        serializedMessage = SerializedScriptValue::createFromWire(message);
    }

    return rv;
}

void MessagePortChannel::close()
{
    MutexLocker lock(m_mutex);
    // Disentangle ourselves from the other end. We still maintain a reference to m_webChannel,
    // since previously-existing messages should still be delivered.
    m_localPort = 0;
    m_entangledChannel = 0;
}

bool MessagePortChannel::isConnectedTo(MessagePort* port)
{
    MutexLocker lock(m_mutex);
    // FIXME: Shouldn't the access to m_entangledChannel->m_localPort be protected by m_entangledChannel->m_mutex?
    return m_entangledChannel && m_entangledChannel->m_localPort == port;
}

bool MessagePortChannel::hasPendingActivity()
{
    MutexLocker lock(m_mutex);
    return m_localPort;
}

void MessagePortChannel::messageAvailable()
{
    MutexLocker lock(m_mutex);
    if (m_localPort)
        m_localPort->messageAvailable();
}

void MessagePortChannel::setEntangledChannel(PassRefPtr<MessagePortChannel> remote)
{
    ASSERT(m_webChannel);
    m_webChannel->entangle(remote->m_webChannel);

    MutexLocker lock(m_mutex);
    m_entangledChannel = remote;
}

WebKit::WebMessagePortChannel* MessagePortChannel::webChannelRelease()
{
    ASSERT(m_webChannel);
    WebKit::WebMessagePortChannel* webChannel = m_webChannel;
    m_webChannel = 0;
    webChannel->setClient(0);
    return webChannel;
}

} // namespace WebCore