Source/core/html/HTMLImportStateResolver.cpp

/*
 * Copyright (C) 2014 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include "config.h"
#include "core/html/HTMLImportStateResolver.h"

#include "core/html/HTMLImport.h"

namespace WebCore {

inline bool HTMLImportStateResolver::isBlockingFollowers(HTMLImport* import)
{
    if (!import->hasLoader())
        return true;
    if (!import->ownsLoader())
        return false;
    return !import->state().isReady();
}

inline bool HTMLImportStateResolver::shouldBlockDocumentCreation() const
{
    // If any of its preceeding imports isn't ready, this import
    // cannot start loading because such preceeding onces can include
    // duplicating import that should wins over this.
    for (const HTMLImport* ancestor = m_import; ancestor; ancestor = ancestor->parent()) {
        if (ancestor->previous() && isBlockingFollowers(ancestor->previous()))
            return true;
    }

    return false;
}

inline bool HTMLImportStateResolver::shouldBlockScriptExecution() const
{
    for (HTMLImport* child = m_import->firstChild(); child; child = child->next()) {
        if (child->isCreatedByParser() && isBlockingFollowers(child))
            return true;
    }

    return false;
}

inline bool HTMLImportStateResolver::isActive() const
{
    return !m_import->isDone();
}

HTMLImportState HTMLImportStateResolver::resolve() const
{
    if (shouldBlockDocumentCreation())
        return HTMLImportState(HTMLImportState::BlockingDocumentCreation);
    if (shouldBlockScriptExecution())
        return HTMLImportState(HTMLImportState::BlockingScriptExecution);
    if (isActive())
        return HTMLImportState(HTMLImportState::Active);
    return HTMLImportState(HTMLImportState::Ready);
}

}