qnetworkaccessbackend.cpp

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#include "qnetworkaccessbackend_p.h"
#include "qnetworkaccessmanager_p.h"
#include "qnetworkconfigmanager.h"
#include "qnetworkrequest.h"
#include "qnetworkreply.h"
#include "qnetworkreply_p.h"
#include "QtCore/qhash.h"
#include "QtCore/qmutex.h"
#include "QtNetwork/private/qnetworksession_p.h"

#include "qnetworkaccesscachebackend_p.h"
#include "qabstractnetworkcache.h"
#include "qhostinfo.h"

#include "private/qnoncontiguousbytedevice_p.h"

QT_BEGIN_NAMESPACE

class QNetworkAccessBackendFactoryData: public QList<QNetworkAccessBackendFactory *>
{
public:
    QNetworkAccessBackendFactoryData() : mutex(QMutex::Recursive)
    {
        valid.ref();
    }
    ~QNetworkAccessBackendFactoryData()
    {
        QMutexLocker locker(&mutex); // why do we need to lock?
        valid.deref();
    }

    QMutex mutex;
    //this is used to avoid (re)constructing factory data from destructors of other global classes
    static QBasicAtomicInt valid;
};
Q_GLOBAL_STATIC(QNetworkAccessBackendFactoryData, factoryData)
QBasicAtomicInt QNetworkAccessBackendFactoryData::valid = Q_BASIC_ATOMIC_INITIALIZER(0);

QNetworkAccessBackendFactory::QNetworkAccessBackendFactory()
{
    QMutexLocker locker(&factoryData()->mutex);
    factoryData()->append(this);
}

QNetworkAccessBackendFactory::~QNetworkAccessBackendFactory()
{
    if (QNetworkAccessBackendFactoryData::valid) {
        QMutexLocker locker(&factoryData()->mutex);
        factoryData()->removeAll(this);
    }
}

QNetworkAccessBackend *QNetworkAccessManagerPrivate::findBackend(QNetworkAccessManager::Operation op,
                                                                 const QNetworkRequest &request)
{
    if (QNetworkAccessBackendFactoryData::valid) {
        QMutexLocker locker(&factoryData()->mutex);
        QNetworkAccessBackendFactoryData::ConstIterator it = factoryData()->constBegin(),
                                                           end = factoryData()->constEnd();
        while (it != end) {
            QNetworkAccessBackend *backend = (*it)->create(op, request);
            if (backend) {
                backend->manager = this;
                return backend; // found a factory that handled our request
            }
            ++it;
        }
    }
    return 0;
}

QNonContiguousByteDevice* QNetworkAccessBackend::createUploadByteDevice()
{
    if (reply->outgoingDataBuffer)
        uploadByteDevice = QSharedPointer<QNonContiguousByteDevice>(QNonContiguousByteDeviceFactory::create(reply->outgoingDataBuffer));
    else if (reply->outgoingData) {
        uploadByteDevice = QSharedPointer<QNonContiguousByteDevice>(QNonContiguousByteDeviceFactory::create(reply->outgoingData));
    } else {
        return 0;
    }

    bool bufferDisallowed =
            reply->request.attribute(QNetworkRequest::DoNotBufferUploadDataAttribute,
                          QVariant(false)) == QVariant(true);
    if (bufferDisallowed)
        uploadByteDevice->disableReset();

    // We want signal emissions only for normal asynchronous uploads
    if (!isSynchronous())
        connect(uploadByteDevice.data(), SIGNAL(readProgress(qint64,qint64)), this, SLOT(emitReplyUploadProgress(qint64,qint64)));

    return uploadByteDevice.data();
}

// need to have this function since the reply is a private member variable
// and the special backends need to access this.
void QNetworkAccessBackend::emitReplyUploadProgress(qint64 bytesSent, qint64 bytesTotal)
{
    if (reply->isFinished)
        return;
    reply->emitUploadProgress(bytesSent, bytesTotal);
}

QNetworkAccessBackend::QNetworkAccessBackend()
    : manager(0)
    , reply(0)
    , synchronous(false)
{
}

QNetworkAccessBackend::~QNetworkAccessBackend()
{
}

void QNetworkAccessBackend::downstreamReadyWrite()
{
    // do nothing
}

void QNetworkAccessBackend::setDownstreamLimited(bool b)
{
    Q_UNUSED(b);
    // do nothing
}

void QNetworkAccessBackend::setReadBufferSize(qint64 size)
{
    Q_UNUSED(size);
    // do nothing
}

void QNetworkAccessBackend::emitReadBufferFreed(qint64 size)
{
    Q_UNUSED(size);
    // do nothing
}

void QNetworkAccessBackend::copyFinished(QIODevice *)
{
    // do nothing
}

void QNetworkAccessBackend::ignoreSslErrors()
{
    // do nothing
}

void QNetworkAccessBackend::ignoreSslErrors(const QList<QSslError> &errors)
{
    Q_UNUSED(errors);
    // do nothing
}

void QNetworkAccessBackend::fetchSslConfiguration(QSslConfiguration &) const
{
    // do nothing
}

void QNetworkAccessBackend::setSslConfiguration(const QSslConfiguration &)
{
    // do nothing
}

QNetworkCacheMetaData QNetworkAccessBackend::fetchCacheMetaData(const QNetworkCacheMetaData &) const
{
    return QNetworkCacheMetaData();
}

QNetworkAccessManager::Operation QNetworkAccessBackend::operation() const
{
    return reply->operation;
}

QNetworkRequest QNetworkAccessBackend::request() const
{
    return reply->request;
}

#ifndef QT_NO_NETWORKPROXY
QList<QNetworkProxy> QNetworkAccessBackend::proxyList() const
{
    return reply->proxyList;
}
#endif

QAbstractNetworkCache *QNetworkAccessBackend::networkCache() const
{
    if (!manager)
        return 0;
    return manager->networkCache;
}

void QNetworkAccessBackend::setCachingEnabled(bool enable)
{
    reply->setCachingEnabled(enable);
}

bool QNetworkAccessBackend::isCachingEnabled() const
{
    return reply->isCachingEnabled();
}

qint64 QNetworkAccessBackend::nextDownstreamBlockSize() const
{
    return reply->nextDownstreamBlockSize();
}

void QNetworkAccessBackend::writeDownstreamData(QByteDataBuffer &list)
{
    reply->appendDownstreamData(list);
}

void QNetworkAccessBackend::writeDownstreamData(QIODevice *data)
{
    reply->appendDownstreamData(data);
}

// not actually appending data, it was already written to the user buffer
void QNetworkAccessBackend::writeDownstreamDataDownloadBuffer(qint64 bytesReceived, qint64 bytesTotal)
{
    reply->appendDownstreamDataDownloadBuffer(bytesReceived, bytesTotal);
}

char* QNetworkAccessBackend::getDownloadBuffer(qint64 size)
{
    return reply->getDownloadBuffer(size);
}

QVariant QNetworkAccessBackend::header(QNetworkRequest::KnownHeaders header) const
{
    return reply->q_func()->header(header);
}

void QNetworkAccessBackend::setHeader(QNetworkRequest::KnownHeaders header, const QVariant &value)
{
    reply->setCookedHeader(header, value);
}

bool QNetworkAccessBackend::hasRawHeader(const QByteArray &headerName) const
{
    return reply->q_func()->hasRawHeader(headerName);
}

QByteArray QNetworkAccessBackend::rawHeader(const QByteArray &headerName) const
{
    return reply->q_func()->rawHeader(headerName);
}

QList<QByteArray> QNetworkAccessBackend::rawHeaderList() const
{
    return reply->q_func()->rawHeaderList();
}

void QNetworkAccessBackend::setRawHeader(const QByteArray &headerName, const QByteArray &headerValue)
{
    reply->setRawHeader(headerName, headerValue);
}

QVariant QNetworkAccessBackend::attribute(QNetworkRequest::Attribute code) const
{
    return reply->q_func()->attribute(code);
}

void QNetworkAccessBackend::setAttribute(QNetworkRequest::Attribute code, const QVariant &value)
{
    if (value.isValid())
        reply->attributes.insert(code, value);
    else
        reply->attributes.remove(code);
}
QUrl QNetworkAccessBackend::url() const
{
    return reply->url;
}

void QNetworkAccessBackend::setUrl(const QUrl &url)
{
    reply->url = url;
}

void QNetworkAccessBackend::finished()
{
    reply->finished();
}

void QNetworkAccessBackend::error(QNetworkReply::NetworkError code, const QString &errorString)
{
    reply->error(code, errorString);
}

#ifndef QT_NO_NETWORKPROXY
void QNetworkAccessBackend::proxyAuthenticationRequired(const QNetworkProxy &proxy,
                                                        QAuthenticator *authenticator)
{
    manager->proxyAuthenticationRequired(this, proxy, authenticator);
}
#endif

void QNetworkAccessBackend::authenticationRequired(QAuthenticator *authenticator)
{
    manager->authenticationRequired(this, authenticator);
}

void QNetworkAccessBackend::metaDataChanged()
{
    reply->metaDataChanged();
}

void QNetworkAccessBackend::redirectionRequested(const QUrl &target)
{
    reply->redirectionRequested(target);
}

void QNetworkAccessBackend::sslErrors(const QList<QSslError> &errors)
{
#ifndef QT_NO_OPENSSL
    reply->sslErrors(errors);
#else
    Q_UNUSED(errors);
#endif
}

bool QNetworkAccessBackend::start()
{
#ifndef QT_NO_BEARERMANAGEMENT
    // For bearer, check if session start is required
    QSharedPointer<QNetworkSession> networkSession(manager->getNetworkSession());
    if (networkSession) {
        // session required
        if (networkSession->isOpen() &&
            networkSession->state() == QNetworkSession::Connected) {
            // Session is already open and ready to use.
            // copy network session down to the backend
            setProperty("_q_networksession", QVariant::fromValue(networkSession));
        } else {
            // Session not ready, but can skip for loopback connections

            // This is not ideal.
            const QString host = reply->url.host();

            if (host == QLatin1String("localhost") ||
                QHostAddress(host) == QHostAddress::LocalHost ||
                QHostAddress(host) == QHostAddress::LocalHostIPv6) {
                // Don't need an open session for localhost access.
            } else {
                // need to wait for session to be opened
                return false;
            }
        }
    }
#endif

#ifndef QT_NO_NETWORKPROXY
#ifndef QT_NO_BEARERMANAGEMENT
    // Get the proxy settings from the network session (in the case of service networks,
    // the proxy settings change depending which AP was activated)
    QNetworkSession *session = networkSession.data();
    QNetworkConfiguration config;
    if (session) {
        QNetworkConfigurationManager configManager;
        // The active configuration tells us what IAP is in use
        QVariant v = session->sessionProperty(QLatin1String("ActiveConfiguration"));
        if (v.isValid())
            config = configManager.configurationFromIdentifier(qvariant_cast<QString>(v));
        // Fallback to using the configuration if no active configuration
        if (!config.isValid())
            config = session->configuration();
        // or unspecified configuration if that is no good either
        if (!config.isValid())
            config = QNetworkConfiguration();
    }
    reply->proxyList = manager->queryProxy(QNetworkProxyQuery(config, url()));
#else // QT_NO_BEARERMANAGEMENT
    // Without bearer management, the proxy depends only on the url
    reply->proxyList = manager->queryProxy(QNetworkProxyQuery(url()));
#endif
#endif

    // now start the request
    open();
    return true;
}

QT_END_NAMESPACE