source: trunk/src/corelib/kernel/qmetaobject.cpp@ 561

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#include "qmetaobject.h"
#include "qmetatype.h"
#include "qobject.h"

#include <qcoreapplication.h>
#include <qcoreevent.h>
#include <qdatastream.h>
#include <qstringlist.h>
#include <qthread.h>
#include <qvarlengtharray.h>
#include <qvariant.h>
#include <qhash.h>
#include <qdebug.h>
#include <qsemaphore.h>

#include "private/qobject_p.h"
#include "private/qmetaobject_p.h"

#include <ctype.h>

QT_BEGIN_NAMESPACE

/*!
    \class QMetaObject

    \brief The QMetaObject class contains meta-information about Qt
    objects.

    \ingroup objectmodel

    The Qt \l{Meta-Object System} in Qt is responsible for the
    signals and slots inter-object communication mechanism, runtime
    type information, and the Qt property system. A single
    QMetaObject instance is created for each QObject subclass that is
    used in an application, and this instance stores all the
    meta-information for the QObject subclass. This object is
    available as QObject::metaObject().

    This class is not normally required for application programming,
    but it is useful if you write meta-applications, such as scripting
    engines or GUI builders.

    The functions you are most likely to find useful are these:
    \list
    \o className() returns the name of a class.
    \o superClass() returns the superclass's meta-object.
    \o method() and methodCount() provide information
       about a class's meta-methods (signals, slots and other
       \l{Q_INVOKABLE}{invokable} member functions).
    \o enumerator() and enumeratorCount() and provide information about
       a class's enumerators.
    \o propertyCount() and property() provide information about a
       class's properties.
    \o constructor() and constructorCount() provide information
       about a class's meta-constructors.
    \endlist

    The index functions indexOfConstructor(), indexOfMethod(),
    indexOfEnumerator(), and indexOfProperty() map names of constructors,
    member functions, enumerators, or properties to indexes in the
    meta-object. For example, Qt uses indexOfMethod() internally when you
    connect a signal to a slot.

    Classes can also have a list of \e{name}--\e{value} pairs of
    additional class information, stored in QMetaClassInfo objects.
    The number of pairs is returned by classInfoCount(), single pairs
    are returned by classInfo(), and you can search for pairs with
    indexOfClassInfo().

    \sa QMetaClassInfo, QMetaEnum, QMetaMethod, QMetaProperty, QMetaType,
        {Meta-Object System}
*/

/*!
    \enum QMetaObject::Call

    \internal

    \value InvokeSlot
    \value EmitSignal
    \value ReadProperty
    \value WriteProperty
    \value ResetProperty
    \value QueryPropertyDesignable
    \value QueryPropertyScriptable
    \value QueryPropertyStored
    \value QueryPropertyEditable
    \value QueryPropertyUser
    \value CreateInstance
*/

/*!
    \enum QMetaMethod::Access

    This enum describes the access level of a method, following the conventions used in C++.

    \value Private
    \value Protected
    \value Public
*/

static inline const QMetaObjectPrivate *priv(const uint* data)
{ return reinterpret_cast<const QMetaObjectPrivate*>(data); }


/*!
    \since 4.5

    Constructs a new instance of this class. You can pass up to ten arguments
    (\a val0, \a val1, \a val2, \a val3, \a val4, \a val5, \a val6, \a val7,
    \a val8, and \a val9) to the constructor. Returns the new object, or 0 if
    no suitable constructor is available.

    Note that only constructors that are declared with the Q_INVOKABLE
    modifier are made available through the meta-object system.

    \sa Q_ARG(), constructor()
*/
QObject *QMetaObject::newInstance(QGenericArgument val0,
                                  QGenericArgument val1,
                                  QGenericArgument val2,
                                  QGenericArgument val3,
                                  QGenericArgument val4,
                                  QGenericArgument val5,
                                  QGenericArgument val6,
                                  QGenericArgument val7,
                                  QGenericArgument val8,
                                  QGenericArgument val9) const
{
    QByteArray constructorName = className();
    {
        int idx = constructorName.lastIndexOf(':');
        if (idx != -1)
            constructorName.remove(0, idx+1); // remove qualified part
    }
    QVarLengthArray<char, 512> sig;
    sig.append(constructorName.constData(), constructorName.length());
    sig.append('(');

    enum { MaximumParamCount = 10 };
    const char *typeNames[] = {val0.name(), val1.name(), val2.name(), val3.name(), val4.name(),
                               val5.name(), val6.name(), val7.name(), val8.name(), val9.name()};

    int paramCount;
    for (paramCount = 0; paramCount < MaximumParamCount; ++paramCount) {
        int len = qstrlen(typeNames[paramCount]);
        if (len <= 0)
            break;
        sig.append(typeNames[paramCount], len);
        sig.append(',');
    }
    if (paramCount == 0)
        sig.append(')'); // no parameters
    else
        sig[sig.size() - 1] = ')';
    sig.append('\0');

    int idx = indexOfConstructor(sig.constData());
    if (idx < 0) {
        QByteArray norm = QMetaObject::normalizedSignature(sig.constData());
        idx = indexOfConstructor(norm.constData());
    }
    if (idx < 0)
        return 0;

    QVariant ret(QMetaType::QObjectStar, (void*)0);
    void *param[] = {ret.data(), val0.data(), val1.data(), val2.data(), val3.data(), val4.data(),
                     val5.data(), val6.data(), val7.data(), val8.data(), val9.data()};

    if (static_metacall(CreateInstance, idx, param) >= 0)
        return 0;
    return *reinterpret_cast<QObject**>(param[0]);
}

/*!
    \internal
*/
int QMetaObject::static_metacall(Call cl, int idx, void **argv) const
{
    if (priv(d.data)->revision < 2)
        return 0;
    const QMetaObjectExtraData *extra = (const QMetaObjectExtraData*)(d.extradata);
    if (!extra || !extra->static_metacall)
        return 0;
    return extra->static_metacall(cl, idx, argv);
}

/*!
    \internal
*/
int QMetaObject::metacall(QObject *object, Call cl, int idx, void **argv)
{
    if (QMetaObject *mo = object->d_ptr->metaObject)
        return static_cast<QAbstractDynamicMetaObject*>(mo)->metaCall(cl, idx, argv);
    else
        return object->qt_metacall(cl, idx, argv);
}

/*!
    \fn const char *QMetaObject::className() const

    Returns the class name.

    \sa superClass()
*/

/*!
    \fn QMetaObject *QMetaObject::superClass() const

    Returns the meta-object of the superclass, or 0 if there is no
    such object.

    \sa className()
*/

/*!
    \internal

    Returns \a obj if object \a obj inherits from this
    meta-object; otherwise returns 0.
*/
QObject *QMetaObject::cast(QObject *obj) const
{
    if (obj) {
        const QMetaObject *m = obj->metaObject();
        do {
            if (m == this)
                return const_cast<QObject*>(obj);
        } while ((m = m->d.superdata));
    }
    return 0;
}

#ifndef QT_NO_TRANSLATION
/*!
    \internal
*/
QString QMetaObject::tr(const char *s, const char *c) const
{
    return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::CodecForTr);
}

/*!
    \internal
*/
QString QMetaObject::tr(const char *s, const char *c, int n) const
{
    return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::CodecForTr, n);
}

/*!
    \internal
*/
QString QMetaObject::trUtf8(const char *s, const char *c) const
{
    return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::UnicodeUTF8);
}

/*!
    \internal
*/
QString QMetaObject::trUtf8(const char *s, const char *c, int n) const
{
    return QCoreApplication::translate(d.stringdata, s, c, QCoreApplication::UnicodeUTF8, n);
}
#endif // QT_NO_TRANSLATION

/*!
    Returns the method offset for this class; i.e. the index position
    of this class's first member function.

    The offset is the sum of all the methods in the class's
    superclasses (which is always positive since QObject has the
    deleteLater() slot and a destroyed() signal).

    \sa method(), methodCount(), indexOfMethod()
*/
int QMetaObject::methodOffset() const
{
    int offset = 0;
    const QMetaObject *m = d.superdata;
    while (m) {
        offset += priv(m->d.data)->methodCount;
        m = m->d.superdata;
    }
    return offset;
}


/*!
    Returns the enumerator offset for this class; i.e. the index
    position of this class's first enumerator.

    If the class has no superclasses with enumerators, the offset is
    0; otherwise the offset is the sum of all the enumerators in the
    class's superclasses.

    \sa enumerator(), enumeratorCount(), indexOfEnumerator()
*/
int QMetaObject::enumeratorOffset() const
{
    int offset = 0;
    const QMetaObject *m = d.superdata;
    while (m) {
        offset += priv(m->d.data)->enumeratorCount;
        m = m->d.superdata;
    }
    return offset;
}

/*!
    Returns the property offset for this class; i.e. the index
    position of this class's first property.

    The offset is the sum of all the properties in the class's
    superclasses (which is always positive since QObject has the
    name() property).

    \sa property(), propertyCount(), indexOfProperty()
*/
int QMetaObject::propertyOffset() const
{
    int offset = 0;
    const QMetaObject *m = d.superdata;
    while (m) {
        offset += priv(m->d.data)->propertyCount;
        m = m->d.superdata;
    }
    return offset;
}

/*!
    Returns the class information offset for this class; i.e. the
    index position of this class's first class information item.

    If the class has no superclasses with class information, the
    offset is 0; otherwise the offset is the sum of all the class
    information items in the class's superclasses.

    \sa classInfo(), classInfoCount(), indexOfClassInfo()
*/
int QMetaObject::classInfoOffset() const
{
    int offset = 0;
    const QMetaObject *m = d.superdata;
    while (m) {
        offset += priv(m->d.data)->classInfoCount;
        m = m->d.superdata;
    }
    return offset;
}

/*!
    \since 4.5

    Returns the number of constructors in this class.

    \sa constructor(), indexOfConstructor()
*/
int QMetaObject::constructorCount() const
{
    if (priv(d.data)->revision < 2)
        return 0;
    return priv(d.data)->constructorCount;
}

/*!
    Returns the number of methods in this class, including the number of
    properties provided by each base class. These include signals and slots
    as well as normal member functions.

    Use code like the following to obtain a QStringList containing the methods
    specific to a given class:

    \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp methodCount

    \sa method(), methodOffset(), indexOfMethod()
*/
int QMetaObject::methodCount() const
{
    int n = priv(d.data)->methodCount;
    const QMetaObject *m = d.superdata;
    while (m) {
        n += priv(m->d.data)->methodCount;
        m = m->d.superdata;
    }
    return n;
}

/*!
    Returns the number of enumerators in this class.

    \sa enumerator(), enumeratorOffset(), indexOfEnumerator()
*/
int QMetaObject::enumeratorCount() const
{
    int n = priv(d.data)->enumeratorCount;
    const QMetaObject *m = d.superdata;
    while (m) {
        n += priv(m->d.data)->enumeratorCount;
        m = m->d.superdata;
    }
    return n;
}

/*!
    Returns the number of properties in this class, including the number of
    properties provided by each base class.

    Use code like the following to obtain a QStringList containing the properties
    specific to a given class:

    \snippet doc/src/snippets/code/src_corelib_kernel_qmetaobject.cpp propertyCount

    \sa property(), propertyOffset(), indexOfProperty()
*/
int QMetaObject::propertyCount() const
{
    int n = priv(d.data)->propertyCount;
    const QMetaObject *m = d.superdata;
    while (m) {
        n += priv(m->d.data)->propertyCount;
        m = m->d.superdata;
    }
    return n;
}

/*!
    Returns the number of items of class information in this class.

    \sa classInfo(), classInfoOffset(), indexOfClassInfo()
*/
int QMetaObject::classInfoCount() const
{
    int n = priv(d.data)->classInfoCount;
    const QMetaObject *m = d.superdata;
    while (m) {
        n += priv(m->d.data)->classInfoCount;
        m = m->d.superdata;
    }
    return n;
}

/*!
    \since 4.5

    Finds \a constructor and returns its index; otherwise returns -1.

    Note that the \a constructor has to be in normalized form, as returned
    by normalizedSignature().

    \sa constructor(), constructorCount(), normalizedSignature()
*/
int QMetaObject::indexOfConstructor(const char *constructor) const
{
    if (priv(d.data)->revision < 2)
        return -1;
    for (int i = priv(d.data)->constructorCount-1; i >= 0; --i) {
        if (strcmp(constructor, d.stringdata
                   + d.data[priv(d.data)->constructorData + 5*i]) == 0) {
            return i;
        }
    }
    return -1;
}

/*!
    Finds \a method and returns its index; otherwise returns -1.

    Note that the \a method has to be in normalized form, as returned
    by normalizedSignature().

    \sa method(), methodCount(), methodOffset(), normalizedSignature()
*/
int QMetaObject::indexOfMethod(const char *method) const
{
    int i = -1;
    const QMetaObject *m = this;
    while (m && i < 0) {
        for (i = priv(m->d.data)->methodCount-1; i >= 0; --i)
            if (strcmp(method, m->d.stringdata
                       + m->d.data[priv(m->d.data)->methodData + 5*i]) == 0) {
                i += m->methodOffset();
                break;
            }
        m = m->d.superdata;
    }
    return i;
}

/*!
    Finds \a signal and returns its index; otherwise returns -1.

    This is the same as indexOfMethod(), except that it will return
    -1 if the method exists but isn't a signal.

    Note that the \a signal has to be in normalized form, as returned
    by normalizedSignature().

    \sa indexOfMethod(), normalizedSignature(), method(), methodCount(), methodOffset()
*/
int QMetaObject::indexOfSignal(const char *signal) const
{
    const QMetaObject *m = this;
    int i = QMetaObjectPrivate::indexOfSignalRelative(&m, signal);
    if (i >= 0)
        i += m->methodOffset();
    return i;
}

/*! \internal
    Same as QMetaObject::indexOfSignal, but the result is the local offset to the base object.

    \a baseObject will be adjusted to the enclosing QMetaObject, or 0 if the signal is not found
*/
int QMetaObjectPrivate::indexOfSignalRelative(const QMetaObject **baseObject, const char *signal)
{
    int i = -1;
    while (*baseObject) {
        const QMetaObject *const m = *baseObject;
        for (i = priv(m->d.data)->methodCount-1; i >= 0; --i)
            if ((m->d.data[priv(m->d.data)->methodData + 5*i + 4] & MethodTypeMask) == MethodSignal
                && strcmp(signal, m->d.stringdata
                + m->d.data[priv(m->d.data)->methodData + 5*i]) == 0) {
                break;
            }
        if (i >= 0)
            break;
        *baseObject = m->d.superdata;
    }
#ifndef QT_NO_DEBUG
    const QMetaObject *m = *baseObject;
    if (i >= 0 && m && m->d.superdata) {
        int conflict = m->d.superdata->indexOfMethod(signal);
        if (conflict >= 0)
            qWarning("QMetaObject::indexOfSignal: signal %s from %s redefined in %s",
                     signal, m->d.superdata->d.stringdata, m->d.stringdata);
    }
#endif
    return i;
}


/*!
    Finds \a slot and returns its index; otherwise returns -1.

    This is the same as indexOfMethod(), except that it will return
    -1 if the method exists but isn't a slot.

    \sa indexOfMethod(), method(), methodCount(), methodOffset()
*/
int QMetaObject::indexOfSlot(const char *slot) const
{
    int i = -1;
    const QMetaObject *m = this;
    while (m && i < 0) {
        for (i = priv(m->d.data)->methodCount-1; i >= 0; --i)
            if ((m->d.data[priv(m->d.data)->methodData + 5*i + 4] & MethodTypeMask) == MethodSlot
                && strcmp(slot, m->d.stringdata
                       + m->d.data[priv(m->d.data)->methodData + 5*i]) == 0) {
                i += m->methodOffset();
                break;
            }
        m = m->d.superdata;
    }
    return i;
}

static const QMetaObject *QMetaObject_findMetaObject(const QMetaObject *self, const char *name)
{
    while (self) {
        if (strcmp(self->d.stringdata, name) == 0)
            return self;
        if (self->d.extradata) {
#ifdef Q_NO_DATA_RELOCATION
            const QMetaObjectAccessor *e;
            Q_ASSERT(priv(self->d.data)->revision >= 2);
#else
            const QMetaObject **e;
            if (priv(self->d.data)->revision < 2) {
                e = (const QMetaObject**)(self->d.extradata);
            } else
#endif
            {
                const QMetaObjectExtraData *extra = (const QMetaObjectExtraData*)(self->d.extradata);
                e = extra->objects;
            }
            if (e) {
                while (*e) {
#ifdef Q_NO_DATA_RELOCATION
                    if (const QMetaObject *m =QMetaObject_findMetaObject(&((*e)()), name))
#else
                    if (const QMetaObject *m =QMetaObject_findMetaObject((*e), name))
#endif
                        return m;
                    ++e;
                }
            }
        }
        self = self->d.superdata;
    }
    return self;
}

/*!
    Finds enumerator \a name and returns its index; otherwise returns
    -1.

    \sa enumerator(), enumeratorCount(), enumeratorOffset()
*/
int QMetaObject::indexOfEnumerator(const char *name) const
{
    int i = -1;
    const QMetaObject *m = this;
    while (m && i < 0) {
        for (i = priv(m->d.data)->enumeratorCount-1; i >= 0; --i)
            if (strcmp(name, m->d.stringdata
                       + m->d.data[priv(m->d.data)->enumeratorData + 4*i]) == 0) {
                i += m->enumeratorOffset();
                break;
            }
        m = m->d.superdata;
    }
    return i;
}

/*!
    Finds property \a name and returns its index; otherwise returns
    -1.

    \sa property(), propertyCount(), propertyOffset()
*/
int QMetaObject::indexOfProperty(const char *name) const
{
    int i = -1;
    const QMetaObject *m = this;
    while (m && i < 0) {
        for (i = priv(m->d.data)->propertyCount-1; i >= 0; --i)
            if (strcmp(name, m->d.stringdata
                       + m->d.data[priv(m->d.data)->propertyData + 3*i]) == 0) {
                i += m->propertyOffset();
                break;
            }
        m = m->d.superdata;
    }

    if (i == -1 && priv(this->d.data)->revision >= 3 && (priv(this->d.data)->flags & DynamicMetaObject)){
        QAbstractDynamicMetaObject *me = 
            const_cast<QAbstractDynamicMetaObject *>(static_cast<const QAbstractDynamicMetaObject *>(this));

        i = me->createProperty(name, 0);
    }

    return i;
}

/*!
    Finds class information item \a name and returns its index;
    otherwise returns -1.

    \sa classInfo(), classInfoCount(), classInfoOffset()
*/
int QMetaObject::indexOfClassInfo(const char *name) const
{
    int i = -1;
    const QMetaObject *m = this;
    while (m && i < 0) {
        for (i = priv(m->d.data)->classInfoCount-1; i >= 0; --i)
            if (strcmp(name, m->d.stringdata
                       + m->d.data[priv(m->d.data)->classInfoData + 2*i]) == 0) {
                i += m->classInfoOffset();
                break;
            }
        m = m->d.superdata;
    }
    return i;
}

/*!
    \since 4.5

    Returns the meta-data for the constructor with the given \a index.

    \sa constructorCount(), newInstance()
*/
QMetaMethod QMetaObject::constructor(int index) const
{
    int i = index;
    QMetaMethod result;
    if (priv(d.data)->revision >= 2 && i >= 0 && i < priv(d.data)->constructorCount) {
        result.mobj = this;
        result.handle = priv(d.data)->constructorData + 5*i;
    }
    return result;
}

/*!
    Returns the meta-data for the method with the given \a index.

    \sa methodCount(), methodOffset(), indexOfMethod()
*/
QMetaMethod QMetaObject::method(int index) const
{
    int i = index;
    i -= methodOffset();
    if (i < 0 && d.superdata)
        return d.superdata->method(index);

    QMetaMethod result;
    if (i >= 0 && i < priv(d.data)->methodCount) {
        result.mobj = this;
        result.handle = priv(d.data)->methodData + 5*i;
    }
    return result;
}

/*!
    Returns the meta-data for the enumerator with the given \a index.

    \sa enumeratorCount(), enumeratorOffset(), indexOfEnumerator()
*/
QMetaEnum QMetaObject::enumerator(int index) const
{
    int i = index;
    i -= enumeratorOffset();
    if (i < 0 && d.superdata)
        return d.superdata->enumerator(index);

    QMetaEnum result;
    if (i >= 0 && i < priv(d.data)->enumeratorCount) {
        result.mobj = this;
        result.handle = priv(d.data)->enumeratorData + 4*i;
    }
    return result;
}

/*!
    Returns the meta-data for the property with the given \a index.
    If no such property exists, a null QMetaProperty is returned.

    \sa propertyCount(), propertyOffset(), indexOfProperty()
*/
QMetaProperty QMetaObject::property(int index) const
{
    int i = index;
    i -= propertyOffset();
    if (i < 0 && d.superdata)
        return d.superdata->property(index);