qdbusintegrator.cpp

来自「奇趣公司比较新的qt/emd版本」· C++ 代码 · 共 1,726 行 · 第 1/5 页

    return result.toLatin1();
}

static bool findObject(const QDBusConnectionPrivate::ObjectTreeNode *root,
                       const QString &fullpath, int &usedLength,
                       QDBusConnectionPrivate::ObjectTreeNode &result)
{
    int start = 0;
    int length = fullpath.length();
    if (fullpath.at(0) == QLatin1Char('/'))
        start = 1;

    // walk the object tree
    const QDBusConnectionPrivate::ObjectTreeNode *node = root;
    while (start < length && node && !(node->flags & QDBusConnection::ExportChildObjects)) {
        int end = fullpath.indexOf(QLatin1Char('/'), start);
        end = (end == -1 ? length : end);
        QStringRef pathComponent(&fullpath, start, end - start);

        QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it =
            qLowerBound(node->children.constBegin(), node->children.constEnd(), pathComponent);
        if (it != node->children.constEnd() && it->name == pathComponent)
            // match
            node = it;
        else
            node = 0;

        start = end + 1;
    }

    // found our object
    usedLength = (start > length ? length : start);
    if (node) {
        if (node->obj || !node->children.isEmpty())
            result = *node;
        else
            // there really is no object here
            // we're just looking at an unused space in the QVector
            node = 0;
    }
    return node;
}

static QObject *findChildObject(const QDBusConnectionPrivate::ObjectTreeNode *root,
                                const QString &fullpath, int start)
{
    int length = fullpath.length();

    // any object in the tree can tell us to switch to its own object tree:
    const QDBusConnectionPrivate::ObjectTreeNode *node = root;
    if (node && node->flags & QDBusConnection::ExportChildObjects) {
        QObject *obj = node->obj;

        while (obj) {
            if (start >= length)
                // we're at the correct level
                return obj;

            int pos = fullpath.indexOf(QLatin1Char('/'), start);
            pos = (pos == -1 ? length : pos);
            QStringRef pathComponent(&fullpath, start, pos - start);

            const QObjectList children = obj->children();

            // find a child with the proper name
            QObject *next = 0;
            QObjectList::ConstIterator it = children.constBegin();
            QObjectList::ConstIterator end = children.constEnd();
            for ( ; it != end; ++it)
                if ((*it)->objectName() == pathComponent) {
                    next = *it;
                    break;
                }

            if (!next)
                break;

            obj = next;
            start = pos + 1;
        }
    }

    // object not found
    return 0;
}

extern QDBUS_EXPORT void qDBusAddSpyHook(QDBusSpyHook);
void qDBusAddSpyHook(QDBusSpyHook hook)
{
    qDBusSpyHookList()->append(hook);
}

extern "C" {
static DBusHandlerResult
qDBusSignalFilter(DBusConnection *connection, DBusMessage *message, void *data)
{
    Q_ASSERT(data);
    Q_UNUSED(connection);
    QDBusConnectionPrivate *d = static_cast<QDBusConnectionPrivate *>(data);
    if (d->mode == QDBusConnectionPrivate::InvalidMode)
        return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

    QDBusMessage amsg = QDBusMessagePrivate::fromDBusMessage(message);
    qDBusDebug() << QThread::currentThread() << "got message:" << amsg;

    return d->handleMessage(amsg) ?
        DBUS_HANDLER_RESULT_HANDLED :
        DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
}
}

bool QDBusConnectionPrivate::handleMessage(const QDBusMessage &amsg)
{
    const QDBusSpyHookList *list = qDBusSpyHookList();
    for (int i = 0; i < list->size(); ++i) {
        qDBusDebug() << "calling the message spy hook";
        (*(*list)[i])(amsg);
    }

    switch (amsg.type()) {
    case QDBusMessage::SignalMessage:
        handleSignal(amsg);
        return true;
        break;
    case QDBusMessage::MethodCallMessage:
        handleObjectCall(amsg);
        return true;
    case QDBusMessage::ReplyMessage:
        // This is most likely an ACK generated by RemoveMatch message
        if (amsg.service() == QLatin1String("org.freedesktop.DBus"))
            return true;

        qWarning("QDBusConnection received a message of type %d that it shouldn't have",
                 amsg.type());
        return false;
    case QDBusMessage::ErrorMessage:
        qWarning("QDBusConnection received a message of type %d that it shouldn't have",
                 amsg.type());
        return false;           // we shouldn't have got them here
    case QDBusMessage::InvalidMessage:
        Q_ASSERT_X(false, "QDBusConnection", "Invalid message found when processing");
        break;
    }

    return false;
}

static void huntAndDestroy(QObject *needle, QDBusConnectionPrivate::ObjectTreeNode &haystack)
{
    QDBusConnectionPrivate::ObjectTreeNode::DataList::Iterator it = haystack.children.begin();
    QDBusConnectionPrivate::ObjectTreeNode::DataList::Iterator end = haystack.children.end();
    for ( ; it != end; ++it)
        huntAndDestroy(needle, *it);

    if (needle == haystack.obj) {
        haystack.obj = 0;
        haystack.flags = 0;
    }
}

static void huntAndEmit(DBusConnection *connection, DBusMessage *msg,
                        QObject *needle, const QDBusConnectionPrivate::ObjectTreeNode &haystack,
                        bool isScriptable, bool isAdaptor, const QString &path = QString())
{
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator it = haystack.children.constBegin();
    QDBusConnectionPrivate::ObjectTreeNode::DataList::ConstIterator end = haystack.children.constEnd();
    for ( ; it != end; ++it)
        huntAndEmit(connection, msg, needle, *it, isScriptable, isAdaptor, path + QLatin1String("/") + it->name);

    if (needle == haystack.obj) {
        // is this a signal we should relay?
        if (isAdaptor && (haystack.flags & QDBusConnection::ExportAdaptors) == 0)
            return;             // no: it comes from an adaptor and we're not exporting adaptors
        else if (!isAdaptor) {
            int mask = isScriptable
                       ? QDBusConnection::ExportScriptableSignals
                       : QDBusConnection::ExportNonScriptableSignals;
            if ((haystack.flags & mask) == 0)
                return;         // signal was not exported
        }

        QByteArray p = path.toLatin1();
        if (p.isEmpty())
            p = "/";
        qDBusDebug() << QThread::currentThread() << "emitting signal at" << p;
        DBusMessage *msg2 = dbus_message_copy(msg);
        dbus_message_set_path(msg2, p);
        dbus_connection_send(connection, msg2, 0);
        dbus_message_unref(msg2);
    }
}

static int findSlot(const QMetaObject *mo, const QByteArray &name, int flags,
                    const QString &signature_, QList<int>& metaTypes)
{
    QByteArray msgSignature = signature_.toLatin1();

    for (int idx = mo->methodCount() - 1 ; idx >= QObject::staticMetaObject.methodCount(); --idx) {
        QMetaMethod mm = mo->method(idx);

        // check access:
        if (mm.access() != QMetaMethod::Public)
            continue;

        // check type:
        // unnecessary, since signals are never public:
        //if (mm.methodType() != QMetaMethod::Slot)
        //    continue;

        // check name:
        QByteArray slotname = mm.signature();
        int paren = slotname.indexOf('(');
        if (paren != name.length() || !slotname.startsWith(name))
            continue;

        int returnType = qDBusNameToTypeId(mm.typeName());
        bool isAsync = qDBusCheckAsyncTag(mm.tag());
        bool isScriptable = mm.attributes() & QMetaMethod::Scriptable;

        // consistency check:
        if (isAsync && returnType != QMetaType::Void)
            continue;

        int inputCount = qDBusParametersForMethod(mm, metaTypes);
        if (inputCount == -1)
            continue;           // problem parsing

        metaTypes[0] = returnType;
        bool hasMessage = false;
        if (inputCount > 0 &&
            metaTypes.at(inputCount) == QDBusMetaTypeId::message) {
            // "no input parameters" is allowed as long as the message meta type is there
            hasMessage = true;
            --inputCount;
        }

        // try to match the parameters
        int i;
        QByteArray reconstructedSignature;
        for (i = 1; i <= inputCount; ++i) {
            const char *typeSignature = QDBusMetaType::typeToSignature( metaTypes.at(i) );
            if (!typeSignature)
                break;          // invalid

            reconstructedSignature += typeSignature;
            if (!msgSignature.startsWith(reconstructedSignature))
                break;
        }

        if (reconstructedSignature != msgSignature)
            continue;           // we didn't match them all

        if (hasMessage)
            ++i;

        // make sure that the output parameters have signatures too
        if (returnType != 0 && QDBusMetaType::typeToSignature(returnType) == 0)
            continue;

        bool ok = true;
        for (int j = i; ok && j < metaTypes.count(); ++j)
            if (QDBusMetaType::typeToSignature(metaTypes.at(i)) == 0)
                ok = false;
        if (!ok)
            continue;

        // consistency check:
        if (isAsync && metaTypes.count() > i + 1)
            continue;

        if (isScriptable && (flags & QDBusConnection::ExportScriptableSlots) == 0)
            continue;           // not exported
        if (!isScriptable && (flags & QDBusConnection::ExportNonScriptableSlots) == 0)
            continue;           // not exported

        // if we got here, this slot matched
        return idx;
    }

    // no slot matched
    return -1;
}

QDBusCallDeliveryEvent* QDBusConnectionPrivate::prepareReply(QObject *object, int idx,
                                                             const QList<int> &metaTypes,
                                                             const QDBusMessage &msg)
{
    Q_ASSERT(object);
    Q_UNUSED(object);

    int n = metaTypes.count() - 1;
    if (metaTypes[n] == QDBusMetaTypeId::message)
        --n;

    // check that types match
    for (int i = 0; i < n; ++i)
        if (metaTypes.at(i + 1) != msg.arguments().at(i).userType() &&
            msg.arguments().at(i).userType() != qMetaTypeId<QDBusArgument>())
            return 0;           // no match

    // we can deliver
    // prepare for the call
    return new QDBusCallDeliveryEvent(QDBusConnection(this), idx, this, msg, metaTypes);
}

void QDBusConnectionPrivate::activateSignal(const QDBusConnectionPrivate::SignalHook& hook,
                                            const QDBusMessage &msg)
{
    // This is called by QDBusConnectionPrivate::handleSignal to deliver a signal
    // that was received from D-Bus
    //
    // Signals are delivered to slots if the parameters match
    // Slots can have less parameters than there are on the message
    // Slots can optionally have one final parameter that is a QDBusMessage
    // Slots receive read-only copies of the message (i.e., pass by value or by const-ref)
    QDBusCallDeliveryEvent *call = prepareReply(hook.obj, hook.midx, hook.params, msg);
    if (call)
        postEventToThread(ActivateSignalAction, hook.obj, call);
}

bool QDBusConnectionPrivate::activateCall(QObject* object, int flags, const QDBusMessage &msg)
{
    // This is called by QDBusConnectionPrivate::handleObjectCall to place a call
    // to a slot on the object.
    //
    // The call is delivered to the first slot that matches the following conditions:
    //  - has the same name as the message's target member
    //  - ALL of the message's types are found in slot's parameter list
    //  - optionally has one more parameter of type QDBusMessage
    // If none match, then the slot of the same name as the message target and with
    // the first type of QDBusMessage is delivered.
    //
    // The D-Bus specification requires that all MethodCall messages be replied to, unless the
    // caller specifically waived this requirement. This means that we inspect if the user slot
    // generated a reply and, if it didn't, we will. Obviously, if the user slot doesn't take a
    // QDBusMessage parameter, it cannot generate a reply.
    //
    // When a return message is generated, the slot's return type, if any, will be placed
    // in the message's first position. If there are non-const reference parameters to the
    // slot, they must appear at the end and will be placed in the subsequent message
    // positions.

    static const char cachePropertyName[] = "_qdbus_slotCache";

    if (!object)
        return false;