Source/core/html/HTMLImportsController.cpp

/*
 * Copyright (C) 2013 Google 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:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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 THE COPYRIGHT
 * OWNER 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 "core/html/HTMLImportsController.h"

#include "core/dom/Document.h"
#include "core/html/HTMLDocument.h"
#include "core/html/HTMLLinkElement.h"
#include "core/loader/CrossOriginAccessControl.h"
#include "core/loader/DocumentWriter.h"
#include "core/loader/cache/CachedScript.h"
#include "core/loader/cache/ResourceFetcher.h"
#include "core/page/ContentSecurityPolicyResponseHeaders.h"
#include "weborigin/SecurityOrigin.h"

namespace WebCore {

PassRefPtr<LinkImport> LinkImport::create(HTMLLinkElement* owner)
{
    return adoptRef(new LinkImport(owner));
}

LinkImport::LinkImport(HTMLLinkElement* owner)
    : LinkResource(owner)
{
}

LinkImport::~LinkImport()
{
}

Document* LinkImport::importedDocument() const
{
    if (!m_loader)
        return 0;
    return m_loader->importedDocument();
}

void LinkImport::process()
{
    if (m_loader)
        return;
    if (!m_owner)
        return;

    if (!m_owner->document()->frame() && !m_owner->document()->import())
        return;

    LinkRequestBuilder builder(m_owner);
    if (!builder.isValid())
        return;

    if (!m_owner->document()->import()) {
        ASSERT(m_owner->document()->frame()); // The document should be the master.
        HTMLImportsController::provideTo(m_owner->document());
    }

    HTMLImport* parent = m_owner->document()->import();
    HTMLImportsController* controller = parent->controller();
    if (RefPtr<HTMLImportLoader> found = controller->findLinkFor(builder.url())) {
        m_loader = found;
        return;
    }

    FetchRequest request = builder.build(true);
    request.setPotentiallyCrossOriginEnabled(controller->securityOrigin(), DoNotAllowStoredCredentials);
    ResourcePtr<CachedRawResource> resource = m_owner->document()->fetcher()->requestImport(request);
    if (!resource)
        return;

    m_loader = HTMLImportLoader::create(parent, builder.url(), resource);
}

void LinkImport::ownerRemoved()
{
    m_owner = 0;
    m_loader.clear();
}


PassRefPtr<HTMLImportLoader> HTMLImportLoader::create(HTMLImport* parent, const KURL& url, const ResourcePtr<CachedScript>& resource)
{
    RefPtr<HTMLImportLoader> loader = adoptRef(new HTMLImportLoader(parent, url, resource));
    loader->controller()->addImport(loader);
    parent->appendChild(loader.get());
    return loader.release();
}

HTMLImportLoader::HTMLImportLoader(HTMLImport* parent, const KURL& url, const ResourcePtr<CachedScript>& resource)
    : m_parent(parent)
    , m_state(StateLoading)
    , m_resource(resource)
    , m_url(url)
{
    m_resource->addClient(this);
}

HTMLImportLoader::~HTMLImportLoader()
{
    // importDestroyed() should be called before the destruction.
    ASSERT(!m_parent);
    ASSERT(!m_importedDocument);
    if (m_resource)
        m_resource->removeClient(this);
}

void HTMLImportLoader::responseReceived(Resource*, const ResourceResponse& response)
{
    setState(startWritingAndParsing(response));
}

void HTMLImportLoader::dataReceived(Resource*, const char* data, int length)
{
    RefPtr<DocumentWriter> protectingWriter(m_writer);
    m_writer->addData(data, length);
}

void HTMLImportLoader::notifyFinished(Resource*)
{
    setState(finishWriting());
}

void HTMLImportLoader::setState(State state)
{
    if (m_state == state)
        return;

    m_state = state;

    if (m_state == StateReady || m_state == StateError || m_state == StateWritten) {
        if (RefPtr<DocumentWriter> writer = m_writer.release())
            writer->end();
    }

    if (m_state == StateReady || m_state == StateError)
        dispose();
}

void HTMLImportLoader::dispose()
{
    if (m_resource) {
        m_resource->removeClient(this);
        m_resource = 0;
    }

    ASSERT(!document() || !document()->parsing());
    controller()->scheduleUnblock();
}

HTMLImportLoader::State HTMLImportLoader::startWritingAndParsing(const ResourceResponse& response)
{
    // Current canAccess() implementation isn't sufficient for catching cross-domain redirects: http://crbug.com/256976
    if (!m_parent->document()->fetcher()->canAccess(m_resource.get()))
        return StateError;

    m_importedDocument = HTMLDocument::create(DocumentInit(response.url(), 0, this).withRegistrationContext(controller()->document()->registrationContext()));
    m_importedDocument->initContentSecurityPolicy(ContentSecurityPolicyResponseHeaders(response));
    m_writer = DocumentWriter::create(m_importedDocument.get(), response.mimeType(), response.textEncodingName());

    return StateLoading;
}

HTMLImportLoader::State HTMLImportLoader::finishWriting()
{
    if (!m_parent)
        return StateError;
    // The writer instance indicates that a part of the document can be already loaded.
    // We don't take such a case as an error because the partially-loaded document has been visible from script at this point.
    if (m_resource->loadFailedOrCanceled() && !m_writer)
        return StateError;

    return StateWritten;
}

HTMLImportLoader::State HTMLImportLoader::finishParsing()
{
    if (!m_parent)
        return StateError;
    return StateReady;
}

Document* HTMLImportLoader::importedDocument() const
{
    if (m_state == StateError)
        return 0;
    return m_importedDocument.get();
}

void HTMLImportLoader::importDestroyed()
{
    m_parent = 0;
    if (RefPtr<Document> document = m_importedDocument.release())
        document->setImport(0);
}

HTMLImportsController* HTMLImportLoader::controller()
{
    return m_parent ? m_parent->controller() : 0;
}

HTMLImport* HTMLImportLoader::parent() const
{
    return m_parent;
}

Document* HTMLImportLoader::document() const
{
    return m_importedDocument.get();
}

void HTMLImportLoader::wasDetachedFromDocument()
{
    // For imported documens this shouldn't be called because Document::m_import is
    // cleared before Document is destroyed by HTMLImportLoader::importDestroyed().
    ASSERT_NOT_REACHED();
}

void HTMLImportLoader::didFinishParsing()
{
    setState(finishParsing());
}

bool HTMLImportLoader::isProcessing() const
{
    if (!m_importedDocument)
        return !isDone();
    return m_importedDocument->parsing();
}

void HTMLImportsController::provideTo(Document* master)
{
    DEFINE_STATIC_LOCAL(const char*, name, ("HTMLImportsController"));
    OwnPtr<HTMLImportsController> controller = adoptPtr(new HTMLImportsController(master));
    master->setImport(controller.get());
    Supplement<ScriptExecutionContext>::provideTo(master, name, controller.release());
}

HTMLImportsController::HTMLImportsController(Document* master)
    : m_master(master)
    , m_unblockTimer(this, &HTMLImportsController::unblockTimerFired)
{
}

HTMLImportsController::~HTMLImportsController()
{
    ASSERT(!m_master);
}

void HTMLImportsController::clear()
{
    for (size_t i = 0; i < m_imports.size(); ++i)
        m_imports[i]->importDestroyed();
    if (m_master)
        m_master->setImport(0);
    m_master = 0;
}

void HTMLImportsController::addImport(PassRefPtr<HTMLImportLoader> link)
{
    ASSERT(!link->url().isEmpty() && link->url().isValid());
    m_imports.append(link);
}

void HTMLImportsController::showSecurityErrorMessage(const String& message)
{
    m_master->addConsoleMessage(JSMessageSource, ErrorMessageLevel, message);
}

PassRefPtr<HTMLImportLoader> HTMLImportsController::findLinkFor(const KURL& url) const
{
    for (size_t i = 0; i < m_imports.size(); ++i) {
        if (equalIgnoringFragmentIdentifier(m_imports[i]->url(), url))
            return m_imports[i];
    }

    return 0;
}

SecurityOrigin* HTMLImportsController::securityOrigin() const
{
    return m_master->securityOrigin();
}

ResourceFetcher* HTMLImportsController::fetcher() const
{
    return m_master->fetcher();
}

HTMLImportsController* HTMLImportsController::controller()
{
    return this;
}

HTMLImport* HTMLImportsController::parent() const
{
    return 0;
}

Document* HTMLImportsController::document() const
{
    return m_master;
}

void HTMLImportsController::wasDetachedFromDocument()
{
    clear();
}

void HTMLImportsController::didFinishParsing()
{
}

bool HTMLImportsController::isProcessing() const
{
    return m_master->parsing();
}

void HTMLImportsController::scheduleUnblock()
{
    if (m_unblockTimer.isActive())
        return;
    m_unblockTimer.startOneShot(0);
}

void HTMLImportsController::unblockTimerFired(Timer<HTMLImportsController>*)
{
    do {
        m_unblockTimer.stop();
        HTMLImport::unblock(this);
    } while (m_unblockTimer.isActive());
}

} // namespace WebCore