qdbusabstractinterface.cpp

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#include "qdbusabstractinterface.h"
#include "qdbusabstractinterface_p.h"

#include <qthread.h>

#include "qdbusargument.h"
#include "qdbuspendingcall.h"
#include "qdbusmessage_p.h"
#include "qdbusmetaobject_p.h"
#include "qdbusmetatype_p.h"
#include "qdbusutil_p.h"

#include <qdebug.h>

#ifndef QT_NO_DBUS

QT_BEGIN_NAMESPACE

static QDBusError checkIfValid(const QString &service, const QString &path,
                               const QString &interface, bool isDynamic, bool isPeer)
{
    // We should be throwing exceptions here... oh well
    QDBusError error;

    // dynamic interfaces (QDBusInterface) can have empty interfaces, but not service and object paths
    // non-dynamic is the opposite: service and object paths can be empty, but not the interface
    if (!isDynamic) {
        // use assertion here because this should never happen, at all
        Q_ASSERT_X(!interface.isEmpty(), "QDBusAbstractInterface", "Interface name cannot be empty");
    }
    if (!QDBusUtil::checkBusName(service, (isDynamic && !isPeer) ? QDBusUtil::EmptyNotAllowed : QDBusUtil::EmptyAllowed, &error))
        return error;
    if (!QDBusUtil::checkObjectPath(path, isDynamic ? QDBusUtil::EmptyNotAllowed : QDBusUtil::EmptyAllowed, &error))
        return error;
    if (!QDBusUtil::checkInterfaceName(interface, QDBusUtil::EmptyAllowed, &error))
        return error;

    // no error
    return QDBusError();
}

QDBusAbstractInterfacePrivate::QDBusAbstractInterfacePrivate(const QString &serv,
                                                             const QString &p,
                                                             const QString &iface,
                                                             const QDBusConnection& con,
                                                             bool isDynamic)
    : connection(con), service(serv), path(p), interface(iface),
      lastError(checkIfValid(serv, p, iface, isDynamic, (connectionPrivate() &&
                                                         connectionPrivate()->mode == QDBusConnectionPrivate::PeerMode))),
      timeout(-1),
      isValid(!lastError.isValid())
{
    if (!isValid)
        return;

    if (!connection.isConnected()) {
        lastError = QDBusError(QDBusError::Disconnected,
                               QLatin1String("Not connected to D-Bus server"));
    } else if (!service.isEmpty()) {
        currentOwner = connectionPrivate()->getNameOwner(service); // verify the name owner
        if (currentOwner.isEmpty()) {
            lastError = connectionPrivate()->lastError;
        }
    }
}

bool QDBusAbstractInterfacePrivate::canMakeCalls() const
{
    // recheck only if we have a wildcard (i.e. empty) service or path
    // if any are empty, set the error message according to QDBusUtil
    if (service.isEmpty() && connectionPrivate()->mode != QDBusConnectionPrivate::PeerMode)
        return QDBusUtil::checkBusName(service, QDBusUtil::EmptyNotAllowed, &lastError);
    if (path.isEmpty())
        return QDBusUtil::checkObjectPath(path, QDBusUtil::EmptyNotAllowed, &lastError);
    return true;
}

void QDBusAbstractInterfacePrivate::property(const QMetaProperty &mp, QVariant &where) const
{
    if (!isValid || !canMakeCalls()) {   // can't make calls
        where.clear();
        return;
    }

    // is this metatype registered?
    const char *expectedSignature = "";
    if (mp.type() != 0xff) {
        expectedSignature = QDBusMetaType::typeToSignature(where.userType());
        if (expectedSignature == 0) {
            qWarning("QDBusAbstractInterface: type %s must be registered with QtDBus before it can be "
                     "used to read property %s.%s",
                     mp.typeName(), qPrintable(interface), mp.name());
            lastError = QDBusError(QDBusError::Failed,
                                   QString::fromLatin1("Unregistered type %1 cannot be handled")
                                   .arg(QLatin1String(mp.typeName())));
            where.clear();
            return;
        }
    }

    // try to read this property
    QDBusMessage msg = QDBusMessage::createMethodCall(service, path,
                                                      QLatin1String(DBUS_INTERFACE_PROPERTIES),
                                                      QLatin1String("Get"));
    QDBusMessagePrivate::setParametersValidated(msg, true);
    msg << interface << QString::fromUtf8(mp.name());
    QDBusMessage reply = connection.call(msg, QDBus::Block, timeout);

    if (reply.type() != QDBusMessage::ReplyMessage) {
        lastError = reply;
        where.clear();
        return;
    }
    if (reply.signature() != QLatin1String("v")) {
        QString errmsg = QLatin1String("Invalid signature `%1' in return from call to "
                                       DBUS_INTERFACE_PROPERTIES);
        lastError = QDBusError(QDBusError::InvalidSignature, errmsg.arg(reply.signature()));
        where.clear();
        return;
    }

    QByteArray foundSignature;
    const char *foundType = 0;
    QVariant value = qvariant_cast<QDBusVariant>(reply.arguments().at(0)).variant();

    if (value.userType() == where.userType() || mp.type() == 0xff
        || (expectedSignature[0] == 'v' && expectedSignature[1] == '\0')) {
        // simple match
        where = value;
        return;
    }

    if (value.userType() == qMetaTypeId<QDBusArgument>()) {
        QDBusArgument arg = qvariant_cast<QDBusArgument>(value);

        foundType = "user type";
        foundSignature = arg.currentSignature().toLatin1();
        if (foundSignature == expectedSignature) {
            // signatures match, we can demarshall
            QDBusMetaType::demarshall(arg, where.userType(), where.data());
            return;
        }
    } else {
        foundType = value.typeName();
        foundSignature = QDBusMetaType::typeToSignature(value.userType());
    }

    // there was an error...
    QString errmsg = QLatin1String("Unexpected `%1' (%2) when retrieving property `%3.%4' "
                                   "(expected type `%5' (%6))");
    lastError = QDBusError(QDBusError::InvalidSignature,
                           errmsg.arg(QString::fromLatin1(foundType),
                                      QString::fromLatin1(foundSignature),
                                      interface,
                                      QString::fromUtf8(mp.name()),
                                      QString::fromLatin1(mp.typeName()),
                                      QString::fromLatin1(expectedSignature)));
    where.clear();
    return;
}

bool QDBusAbstractInterfacePrivate::setProperty(const QMetaProperty &mp, const QVariant &value)
{
    if (!isValid || !canMakeCalls())    // can't make calls
        return false;

    // send the value
    QDBusMessage msg = QDBusMessage::createMethodCall(service, path,
                                                QLatin1String(DBUS_INTERFACE_PROPERTIES),
                                                QLatin1String("Set"));
    QDBusMessagePrivate::setParametersValidated(msg, true);
    msg << interface << QString::fromUtf8(mp.name()) << QVariant::fromValue(QDBusVariant(value));
    QDBusMessage reply = connection.call(msg, QDBus::Block, timeout);

    if (reply.type() != QDBusMessage::ReplyMessage) {
        lastError = reply;
        return false;
    }
    return true;
}

void QDBusAbstractInterfacePrivate::_q_serviceOwnerChanged(const QString &name,
                                                           const QString &oldOwner,
                                                           const QString &newOwner)
{
    Q_UNUSED(oldOwner);
    //qDebug() << "QDBusAbstractInterfacePrivate serviceOwnerChanged" << name << oldOwner << newOwner;
    if (name == service) {
        currentOwner = newOwner;
    }
}

QDBusAbstractInterfaceBase::QDBusAbstractInterfaceBase(QDBusAbstractInterfacePrivate &d, QObject *parent)
    : QObject(d, parent)
{
}

int QDBusAbstractInterfaceBase::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
{
    int saved_id = _id;
    _id = QObject::qt_metacall(_c, _id, _a);
    if (_id < 0)
        return _id;

    if (_c == QMetaObject::ReadProperty || _c == QMetaObject::WriteProperty) {
        QMetaProperty mp = metaObject()->property(saved_id);
        int &status = *reinterpret_cast<int *>(_a[2]);
        QVariant &variant = *reinterpret_cast<QVariant *>(_a[1]);

        if (_c == QMetaObject::WriteProperty) {
            status = d_func()->setProperty(mp, variant) ? 1 : 0;
        } else {
            d_func()->property(mp, variant);
            status = variant.isValid() ? 1 : 0;
        }
        _id = -1;
    }
    return _id;
}

QDBusAbstractInterface::QDBusAbstractInterface(QDBusAbstractInterfacePrivate &d, QObject *parent)
    : QDBusAbstractInterfaceBase(d, parent)
{
    // keep track of the service owner
    if (d.isValid &&
        d.connection.isConnected()
        && !d.service.isEmpty()
        && !d.service.startsWith(QLatin1Char(':')))
        d_func()->connection.connect(QLatin1String(DBUS_SERVICE_DBUS), // service
                                     QString(), // path
                                     QLatin1String(DBUS_INTERFACE_DBUS), // interface
                                     QLatin1String("NameOwnerChanged"),
                                     QStringList() << d.service,
                                     QString(), // signature
                                     this, SLOT(_q_serviceOwnerChanged(QString,QString,QString)));
}

QDBusAbstractInterface::QDBusAbstractInterface(const QString &service, const QString &path,
                                               const char *interface, const QDBusConnection &con,
                                               QObject *parent)
    : QDBusAbstractInterfaceBase(*new QDBusAbstractInterfacePrivate(service, path, QString::fromLatin1(interface),
                                                 con, false), parent)
{
    // keep track of the service owner
    if (d_func()->isValid &&
        d_func()->connection.isConnected()
        && !service.isEmpty()
        && !service.startsWith(QLatin1Char(':')))
        d_func()->connection.connect(QLatin1String(DBUS_SERVICE_DBUS), // service
                                     QString(), // path
                                     QLatin1String(DBUS_INTERFACE_DBUS), // interface
                                     QLatin1String("NameOwnerChanged"),
                                     QStringList() << service,
                                     QString(), //signature
                                     this, SLOT(_q_serviceOwnerChanged(QString,QString,QString)));
}

QDBusAbstractInterface::~QDBusAbstractInterface()
{
}

bool QDBusAbstractInterface::isValid() const
{
    return !d_func()->currentOwner.isEmpty();
}

QDBusConnection QDBusAbstractInterface::connection() const
{
    return d_func()->connection;
}

QString QDBusAbstractInterface::service() const
{
    return d_func()->service;
}

QString QDBusAbstractInterface::path() const
{
    return d_func()->path;
}

QString QDBusAbstractInterface::interface() const
{
    return d_func()->interface;
}

QDBusError QDBusAbstractInterface::lastError() const
{
    return d_func()->lastError;
}

void QDBusAbstractInterface::setTimeout(int timeout)
{
    d_func()->timeout = timeout;
}

int QDBusAbstractInterface::timeout() const
{
    return d_func()->timeout;
}

QDBusMessage QDBusAbstractInterface::callWithArgumentList(QDBus::CallMode mode,
                                                          const QString& method,
                                                          const QList<QVariant>& args)
{
    Q_D(QDBusAbstractInterface);

    if (!d->isValid || !d->canMakeCalls())
        return QDBusMessage::createError(d->lastError);

    QString m = method;
    // split out the signature from the method
    int pos = method.indexOf(QLatin1Char('.'));
    if (pos != -1)
        m.truncate(pos);

    if (mode == QDBus::AutoDetect) {
        // determine if this a sync or async call
        mode = QDBus::Block;
        const QMetaObject *mo = metaObject();
        QByteArray match = m.toLatin1() + '(';

        for (int i = staticMetaObject.methodCount(); i < mo->methodCount(); ++i) {
            QMetaMethod mm = mo->method(i);
            if (QByteArray(mm.signature()).startsWith(match)) {
                // found a method with the same name as what we're looking for
                // hopefully, nobody is overloading asynchronous and synchronous methods with
                // the same name

                QList<QByteArray> tags = QByteArray(mm.tag()).split(' ');
                if (tags.contains("Q_NOREPLY"))
                    mode = QDBus::NoBlock;

                break;
            }
        }
    }

//    qDebug() << "QDBusAbstractInterface" << "Service" << service() << "Path:" << path();
    QDBusMessage msg = QDBusMessage::createMethodCall(service(), path(), interface(), m);
    QDBusMessagePrivate::setParametersValidated(msg, true);
    msg.setArguments(args);

    QDBusMessage reply = d->connection.call(msg, mode, d->timeout);
    if (thread() == QThread::currentThread())
        d->lastError = reply;       // will clear if reply isn't an error

    // ensure that there is at least one element
    if (reply.arguments().isEmpty())
        reply << QVariant();

    return reply;
}

QDBusPendingCall QDBusAbstractInterface::asyncCallWithArgumentList(const QString& method,
                                                                   const QList<QVariant>& args)
{
    Q_D(QDBusAbstractInterface);

    if (!d->isValid || !d->canMakeCalls())
        return QDBusPendingCall::fromError(d->lastError);

    QDBusMessage msg = QDBusMessage::createMethodCall(service(), path(), interface(), method);
    QDBusMessagePrivate::setParametersValidated(msg, true);
    msg.setArguments(args);
    return d->connection.asyncCall(msg, d->timeout);
}

bool QDBusAbstractInterface::callWithCallback(const QString &method,
                                              const QList<QVariant> &args,
                                              QObject *receiver,
                                              const char *returnMethod,
                                              const char *errorMethod)
{
    Q_D(QDBusAbstractInterface);

    if (!d->isValid || !d->canMakeCalls())
        return false;

    QDBusMessage msg = QDBusMessage::createMethodCall(service(),
                                                      path(),
                                                      interface(),
                                                      method);
    QDBusMessagePrivate::setParametersValidated(msg, true);
    msg.setArguments(args);

    d->lastError = 0;
    return d->connection.callWithCallback(msg,
                                          receiver,
                                          returnMethod,
                                          errorMethod,
                                          d->timeout);
}

bool QDBusAbstractInterface::callWithCallback(const QString &method,
                                              const QList<QVariant> &args,
                                              QObject *receiver,
                                              const char *slot)
{
    return callWithCallback(method, args, receiver, slot, 0);
}

void QDBusAbstractInterface::connectNotify(const char *signal)
{
    // someone connecting to one of our signals
    Q_D(QDBusAbstractInterface);
    if (!d->isValid)
        return;

    // we end up recursing here, so optimize away
    if (qstrcmp(signal + 1, "destroyed(QObject*)") == 0)
        return;

    QDBusConnectionPrivate *conn = d->connectionPrivate();
    if (conn) {
        conn->connectRelay(d->service, d->path, d->interface,
                           this, signal);
    }
}

void QDBusAbstractInterface::disconnectNotify(const char *signal)
{
    // someone disconnecting from one of our signals
    Q_D(QDBusAbstractInterface);
    if (!d->isValid)
        return;

    QDBusConnectionPrivate *conn = d->connectionPrivate();
    if (conn)
        conn->disconnectRelay(d->service, d->path, d->interface,
                              this, signal);
}

QVariant QDBusAbstractInterface::internalPropGet(const char *propname) const
{
    // assume this property exists and is readable
    // we're only called from generated code anyways

    return property(propname);
}

void QDBusAbstractInterface::internalPropSet(const char *propname, const QVariant &value)
{
    setProperty(propname, value);
}

QDBusMessage QDBusAbstractInterface::call(const QString &method, const QVariant &arg1,
                                          const QVariant &arg2,
                                          const QVariant &arg3,
                                          const QVariant &arg4,
                                          const QVariant &arg5,
                                          const QVariant &arg6,
                                          const QVariant &arg7,
                                          const QVariant &arg8)
{
    return call(QDBus::AutoDetect, method, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8);
}

QDBusMessage QDBusAbstractInterface::call(QDBus::CallMode mode, const QString &method,
                                          const QVariant &arg1,
                                          const QVariant &arg2,
                                          const QVariant &arg3,
                                          const QVariant &arg4,
                                          const QVariant &arg5,
                                          const QVariant &arg6,
                                          const QVariant &arg7,
                                          const QVariant &arg8)
{
    QList<QVariant> argList;
    int count = 0 + arg1.isValid() + arg2.isValid() + arg3.isValid() + arg4.isValid() +
                arg5.isValid() + arg6.isValid() + arg7.isValid() + arg8.isValid();

    switch (count) {
    case 8:
        argList.prepend(arg8);
    case 7:
        argList.prepend(arg7);
    case 6:
        argList.prepend(arg6);
    case 5:
        argList.prepend(arg5);
    case 4:
        argList.prepend(arg4);
    case 3:
        argList.prepend(arg3);
    case 2:
        argList.prepend(arg2);
    case 1:
        argList.prepend(arg1);
    }

    return callWithArgumentList(mode, method, argList);
}


QDBusPendingCall QDBusAbstractInterface::asyncCall(const QString &method, const QVariant &arg1,
                                                   const QVariant &arg2,
                                                   const QVariant &arg3,
                                                   const QVariant &arg4,
                                                   const QVariant &arg5,
                                                   const QVariant &arg6,
                                                   const QVariant &arg7,
                                                   const QVariant &arg8)
{
    QList<QVariant> argList;
    int count = 0 + arg1.isValid() + arg2.isValid() + arg3.isValid() + arg4.isValid() +
                arg5.isValid() + arg6.isValid() + arg7.isValid() + arg8.isValid();

    switch (count) {
    case 8:
        argList.prepend(arg8);
    case 7:
        argList.prepend(arg7);
    case 6:
        argList.prepend(arg6);
    case 5:
        argList.prepend(arg5);
    case 4:
        argList.prepend(arg4);
    case 3:
        argList.prepend(arg3);
    case 2:
        argList.prepend(arg2);
    case 1:
        argList.prepend(arg1);
    }

    return asyncCallWithArgumentList(method, argList);
}

QDBusMessage QDBusAbstractInterface::internalConstCall(QDBus::CallMode mode,
                                                       const QString &method,
                                                       const QList<QVariant> &args) const
{
    // ### move the code here, and make the other functions call this
    return const_cast<QDBusAbstractInterface*>(this)->callWithArgumentList(mode, method, args);
}

QT_END_NAMESPACE

#endif // QT_NO_DBUS

#include "moc_qdbusabstractinterface.cpp"