/*

 * Copyright (C) 2007 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. 

 */

#include "config.h"

#include "WebDocumentLoader.h"

using namespace WebCore;

WebDocumentLoader::WebDocumentLoader(const ResourceRequest& request, const SubstituteData& substituteData)

    : DocumentLoader(request, substituteData)

    , m_dataSource(0)

    , m_detachedDataSource(0)

{

}

WebDocumentLoader::~WebDocumentLoader()

{

    if (m_dataSource) {

        ASSERT(!m_detachedDataSource);

        m_dataSource->Release();

    }

}

void WebDocumentLoader::setDataSource(WebDataSource *dataSource)

{

    ASSERT(!m_dataSource);

    m_dataSource = dataSource;

    if (m_dataSource)

        m_dataSource->AddRef();

}

WebDataSource* WebDocumentLoader::dataSource() const

{

    return m_dataSource;

}

void WebDocumentLoader::detachDataSource()

{

    // we only call detachDataSource when the WebDataSource is freed - and we won't get there if m_dataSource is not

    // null (because that would mean the loader still has a reference to the data source)

    ASSERT(!m_dataSource);

    m_detachedDataSource = 0;

}

void WebDocumentLoader::attachToFrame()

{

    DocumentLoader::attachToFrame();

    if (m_detachedDataSource) {

        ASSERT(!m_dataSource);

        setDataSource(m_detachedDataSource);

        m_detachedDataSource = 0;

    }

}

void WebDocumentLoader::detachFromFrame()

{

    DocumentLoader::detachFromFrame();

    m_detachedDataSource = m_dataSource;

    if (m_dataSource) {

        WebDataSource* dataSourceToBeReleased = m_dataSource;

        // It's important to null out m_dataSource before calling release on the data source.  That release can cause the data

        // source to be deleted - which ends up calling loader->detachDataSource() which makes the assumption that the loader no 

        // longer holds a reference to the data source.

        m_dataSource = 0;

        dataSourceToBeReleased->Release();

    }

}