qdbusmetatype.cpp

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** This file is part of the QtDBus module of the Qt Toolkit.
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#include "qdbusmetatype.h"

#include <string.h>
#include "qdbus_symbols_p.h"

#include <qbytearray.h>
#include <qglobal.h>
#include <qreadwritelock.h>
#include <qvector.h>

#include "qdbusmessage.h"
#include "qdbusunixfiledescriptor.h"
#include "qdbusutil_p.h"
#include "qdbusmetatype_p.h"
#include "qdbusargument_p.h"

#ifndef QT_NO_DBUS

#ifndef DBUS_TYPE_UNIX_FD
# define DBUS_TYPE_UNIX_FD int('h')
# define DBUS_TYPE_UNIX_FD_AS_STRING "h"
#endif

Q_DECLARE_METATYPE(QList<bool>)
Q_DECLARE_METATYPE(QList<short>)
Q_DECLARE_METATYPE(QList<ushort>)
Q_DECLARE_METATYPE(QList<int>)
Q_DECLARE_METATYPE(QList<uint>)
Q_DECLARE_METATYPE(QList<qlonglong>)
Q_DECLARE_METATYPE(QList<qulonglong>)
Q_DECLARE_METATYPE(QList<double>)

QT_BEGIN_NAMESPACE

class QDBusCustomTypeInfo
{
public:
    QDBusCustomTypeInfo() : signature(0, '\0'), marshall(0), demarshall(0)
    { }

    // Suggestion:
    // change 'signature' to char* and make QDBusCustomTypeInfo a Movable type
    QByteArray signature;
    QDBusMetaType::MarshallFunction marshall;
    QDBusMetaType::DemarshallFunction demarshall;
};

template<typename T>
inline static void registerHelper(T * = 0)
{
    void (*mf)(QDBusArgument &, const T *) = qDBusMarshallHelper<T>;
    void (*df)(const QDBusArgument &, T *) = qDBusDemarshallHelper<T>;
    QDBusMetaType::registerMarshallOperators(qMetaTypeId<T>(),
        reinterpret_cast<QDBusMetaType::MarshallFunction>(mf),
        reinterpret_cast<QDBusMetaType::DemarshallFunction>(df));
}

int QDBusMetaTypeId::message;
int QDBusMetaTypeId::argument;
int QDBusMetaTypeId::variant;
int QDBusMetaTypeId::objectpath;
int QDBusMetaTypeId::signature;
int QDBusMetaTypeId::error;
int QDBusMetaTypeId::unixfd;

void QDBusMetaTypeId::init()
{
    static volatile bool initialized = false;

    // reentrancy is not a problem since everything else is locked on their own
    // set the guard variable at the end
    if (!initialized) {
        // register our types with QtCore
        message = qRegisterMetaType<QDBusMessage>("QDBusMessage");
        argument = qRegisterMetaType<QDBusArgument>("QDBusArgument");
        variant = qRegisterMetaType<QDBusVariant>("QDBusVariant");
        objectpath = qRegisterMetaType<QDBusObjectPath>("QDBusObjectPath");
        signature = qRegisterMetaType<QDBusSignature>("QDBusSignature");
        error = qRegisterMetaType<QDBusError>("QDBusError");
        unixfd = qRegisterMetaType<QDBusUnixFileDescriptor>("QDBusUnixFileDescriptor");

#ifndef QDBUS_NO_SPECIALTYPES
        // and register QtCore's with us
        registerHelper<QDate>();
        registerHelper<QTime>();
        registerHelper<QDateTime>();
        registerHelper<QRect>();
        registerHelper<QRectF>();
        registerHelper<QSize>();
        registerHelper<QSizeF>();
        registerHelper<QPoint>();
        registerHelper<QPointF>();
        registerHelper<QLine>();
        registerHelper<QLineF>();
        registerHelper<QVariantList>();
        registerHelper<QVariantMap>();
        registerHelper<QVariantHash>();

        qDBusRegisterMetaType<QList<bool> >();
        qDBusRegisterMetaType<QList<short> >();
        qDBusRegisterMetaType<QList<ushort> >();
        qDBusRegisterMetaType<QList<int> >();
        qDBusRegisterMetaType<QList<uint> >();
        qDBusRegisterMetaType<QList<qlonglong> >();
        qDBusRegisterMetaType<QList<qulonglong> >();
        qDBusRegisterMetaType<QList<double> >();
        qDBusRegisterMetaType<QList<QDBusObjectPath> >();
        qDBusRegisterMetaType<QList<QDBusSignature> >();
        qDBusRegisterMetaType<QList<QDBusUnixFileDescriptor> >();
#endif

        initialized = true;
    }
}

Q_GLOBAL_STATIC(QVector<QDBusCustomTypeInfo>, customTypes)
Q_GLOBAL_STATIC(QReadWriteLock, customTypesLock)


void QDBusMetaType::registerMarshallOperators(int id, MarshallFunction mf,
                                              DemarshallFunction df)
{
    QByteArray var;
    QVector<QDBusCustomTypeInfo> *ct = customTypes();
    if (id < 0 || !mf || !df || !ct)
        return;                 // error!

    QWriteLocker locker(customTypesLock());
    if (id >= ct->size())
        ct->resize(id + 1);
    QDBusCustomTypeInfo &info = (*ct)[id];
    info.marshall = mf;
    info.demarshall = df;
}

bool QDBusMetaType::marshall(QDBusArgument &arg, int id, const void *data)
{
    QDBusMetaTypeId::init();

    MarshallFunction mf;
    {
        QReadLocker locker(customTypesLock());
        QVector<QDBusCustomTypeInfo> *ct = customTypes();
        if (id >= ct->size())
            return false;       // non-existent

        const QDBusCustomTypeInfo &info = (*ct).at(id);
        if (!info.marshall) {
            mf = 0;             // make gcc happy
            return false;
        } else
            mf = info.marshall;
    }

    mf(arg, data);
    return true;
}

bool QDBusMetaType::demarshall(const QDBusArgument &arg, int id, void *data)
{
    QDBusMetaTypeId::init();

    DemarshallFunction df;
    {
        QReadLocker locker(customTypesLock());
        QVector<QDBusCustomTypeInfo> *ct = customTypes();
        if (id >= ct->size())
            return false;       // non-existent

        const QDBusCustomTypeInfo &info = (*ct).at(id);
        if (!info.demarshall) {
            df = 0;             // make gcc happy
            return false;
        } else
            df = info.demarshall;
    }

    QDBusArgument copy = arg;
    df(copy, data);
    return true;
}

int QDBusMetaType::signatureToType(const char *signature)
{
    if (!signature)
        return QVariant::Invalid;

    QDBusMetaTypeId::init();
    switch (signature[0])
    {
    case DBUS_TYPE_BOOLEAN:
        return QVariant::Bool;

    case DBUS_TYPE_BYTE:
        return QMetaType::UChar;

    case DBUS_TYPE_INT16:
        return QMetaType::Short;

    case DBUS_TYPE_UINT16:
        return QMetaType::UShort;

    case DBUS_TYPE_INT32:
        return QVariant::Int;

    case DBUS_TYPE_UINT32:
        return QVariant::UInt;

    case DBUS_TYPE_INT64:
        return QVariant::LongLong;

    case DBUS_TYPE_UINT64:
        return QVariant::ULongLong;

    case DBUS_TYPE_DOUBLE:
        return QVariant::Double;

    case DBUS_TYPE_STRING:
        return QVariant::String;

    case DBUS_TYPE_OBJECT_PATH:
        return QDBusMetaTypeId::objectpath;

    case DBUS_TYPE_SIGNATURE:
        return QDBusMetaTypeId::signature;

    case DBUS_TYPE_UNIX_FD:
        return QDBusMetaTypeId::unixfd;

    case DBUS_TYPE_VARIANT:
        return QDBusMetaTypeId::variant;

    case DBUS_TYPE_ARRAY:       // special case
        switch (signature[1]) {
        case DBUS_TYPE_BYTE:
            return QVariant::ByteArray;

        case DBUS_TYPE_STRING:
            return QVariant::StringList;

        case DBUS_TYPE_VARIANT:
            return QVariant::List;

        case DBUS_TYPE_OBJECT_PATH:
            return qMetaTypeId<QList<QDBusObjectPath> >();

        case DBUS_TYPE_SIGNATURE:
            return qMetaTypeId<QList<QDBusSignature> >();

        }
        // fall through
    default:
        return QVariant::Invalid;
    }
}

const char *QDBusMetaType::typeToSignature(int type)
{
    // check if it's a static type
    switch (type)
    {
    case QMetaType::UChar:
        return DBUS_TYPE_BYTE_AS_STRING;

    case QVariant::Bool:
        return DBUS_TYPE_BOOLEAN_AS_STRING;

    case QMetaType::Short:
        return DBUS_TYPE_INT16_AS_STRING;

    case QMetaType::UShort:
        return DBUS_TYPE_UINT16_AS_STRING;

    case QVariant::Int:
        return DBUS_TYPE_INT32_AS_STRING;

    case QVariant::UInt:
        return DBUS_TYPE_UINT32_AS_STRING;

    case QVariant::LongLong:
        return DBUS_TYPE_INT64_AS_STRING;

    case QVariant::ULongLong:
        return DBUS_TYPE_UINT64_AS_STRING;

    case QVariant::Double:
        return DBUS_TYPE_DOUBLE_AS_STRING;

    case QVariant::String:
        return DBUS_TYPE_STRING_AS_STRING;

    case QVariant::StringList:
        return DBUS_TYPE_ARRAY_AS_STRING
            DBUS_TYPE_STRING_AS_STRING; // as

    case QVariant::ByteArray:
        return DBUS_TYPE_ARRAY_AS_STRING
            DBUS_TYPE_BYTE_AS_STRING; // ay
    }

    QDBusMetaTypeId::init();
    if (type == QDBusMetaTypeId::variant)
        return DBUS_TYPE_VARIANT_AS_STRING;
    else if (type == QDBusMetaTypeId::objectpath)
        return DBUS_TYPE_OBJECT_PATH_AS_STRING;
    else if (type == QDBusMetaTypeId::signature)
        return DBUS_TYPE_SIGNATURE_AS_STRING;
    else if (type == QDBusMetaTypeId::unixfd)
        return DBUS_TYPE_UNIX_FD_AS_STRING;

    // try the database
    QVector<QDBusCustomTypeInfo> *ct = customTypes();
    {
        QReadLocker locker(customTypesLock());
        if (type >= ct->size())
            return 0;           // type not registered with us

        const QDBusCustomTypeInfo &info = (*ct).at(type);

        if (!info.signature.isNull())
            return info.signature;

        if (!info.marshall)
            return 0;           // type not registered with us
    }

    // call to user code to construct the signature type
    QDBusCustomTypeInfo *info;
    {
        // createSignature will never return a null QByteArray
        // if there was an error, it'll return ""
        QByteArray signature = QDBusArgumentPrivate::createSignature(type);

        // re-acquire lock
        QWriteLocker locker(customTypesLock());
        info = &(*ct)[type];
        info->signature = signature;
    }
    return info->signature;
}

QT_END_NAMESPACE

#endif // QT_NO_DBUS