qt6-bb10/src/dbus/qdbusmetatype.cpp

487 lines
13 KiB
C++

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qdbusmetatype.h"
#include "qdbusmetatype_p.h"
#include <string.h>
#include "qdbus_symbols_p.h"
#include <qbytearray.h>
#include <qglobal.h>
#include <qlist.h>
#include <qreadwritelock.h>
#include <qdatetime.h>
#include <qrect.h>
#include <qsize.h>
#include <qpoint.h>
#include <qline.h>
#include "qdbusargument_p.h"
#include "qdbusutil_p.h"
#include "qdbusunixfiledescriptor.h"
#ifndef QT_BOOTSTRAPPED
#include "qdbusmessage.h"
#endif
#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
QT_BEGIN_NAMESPACE
class QDBusCustomTypeInfo
{
public:
QDBusCustomTypeInfo() : signature(), marshall(nullptr), demarshall(nullptr)
{ }
// Suggestion:
// change 'signature' to char* and make QDBusCustomTypeInfo a Movable type
QByteArray signature;
QDBusMetaType::MarshallFunction marshall;
QDBusMetaType::DemarshallFunction demarshall;
};
void QDBusMetaTypeId::init()
{
Q_CONSTINIT static QBasicAtomicInt initialized = Q_BASIC_ATOMIC_INITIALIZER(false);
// reentrancy is not a problem since everything else is locked on their own
// set the guard variable at the end
if (!initialized.loadRelaxed()) {
// register our types with Qt Core
message().registerType();
argument().registerType();
variant().registerType();
objectpath().registerType();
signature().registerType();
error().registerType();
unixfd().registerType();
#ifndef QDBUS_NO_SPECIALTYPES
// and register Qt Core's with us
qDBusRegisterMetaType<QDate>();
qDBusRegisterMetaType<QTime>();
qDBusRegisterMetaType<QDateTime>();
qDBusRegisterMetaType<QRect>();
qDBusRegisterMetaType<QRectF>();
qDBusRegisterMetaType<QSize>();
qDBusRegisterMetaType<QSizeF>();
qDBusRegisterMetaType<QPoint>();
qDBusRegisterMetaType<QPointF>();
qDBusRegisterMetaType<QLine>();
qDBusRegisterMetaType<QLineF>();
qDBusRegisterMetaType<QVariantList>();
qDBusRegisterMetaType<QVariantMap>();
qDBusRegisterMetaType<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> >();
// plus lists of our own types
qDBusRegisterMetaType<QList<QDBusVariant> >();
qDBusRegisterMetaType<QList<QDBusObjectPath> >();
qDBusRegisterMetaType<QList<QDBusSignature> >();
qDBusRegisterMetaType<QList<QDBusUnixFileDescriptor> >();
#endif
initialized.storeRelaxed(true);
}
}
struct QDBusCustomTypes
{
QReadWriteLock lock;
QHash<int, QDBusCustomTypeInfo> hash;
};
Q_GLOBAL_STATIC(QDBusCustomTypes, customTypes)
/*!
\class QDBusMetaType
\inmodule QtDBus
\brief Meta-type registration system for the Qt D-Bus module.
\internal
The QDBusMetaType class allows you to register class types for
marshalling and demarshalling over D-Bus. D-Bus supports a very
limited set of primitive types, but allows one to extend the type
system by creating compound types, such as arrays (lists) and
structs. In order to use them with Qt D-Bus, those types must be
registered.
See \l {qdbustypesystem.html}{Qt D-Bus Type System} for more
information on the type system and how to register additional
types.
\sa {qdbustypesystem.html}{Qt D-Bus Type System},
qDBusRegisterMetaType(), QMetaType, QVariant, QDBusArgument
*/
/*!
\fn template<typename T> QMetaType qDBusRegisterMetaType()
\relates QDBusArgument
\threadsafe
\since 4.2
Registers \c{T} with the
\l {qdbustypesystem.html}{Qt D-Bus Type System} and the Qt \l
{QMetaType}{meta-type system}, if it's not already registered.
To register a type, it must be declared as a meta-type with the
Q_DECLARE_METATYPE() macro, and then registered as in the
following example:
\snippet code/src_qdbus_qdbusmetatype.cpp 0-0
\codeline
\snippet code/src_qdbus_qdbusmetatype.cpp 0-1
If \c{T} isn't one of
Qt's \l{container classes}, the \c{operator<<} and
\c{operator>>} streaming operators between \c{T} and QDBusArgument
must be already declared. See the \l {qdbustypesystem.html}{Qt D-Bus
Type System} page for more information on how to declare such
types.
This function returns the Qt meta type id for the type (the same
value that is returned from qRegisterMetaType()).
\note The feature that a \c{T} inheriting a streamable type (including
the containers QList, QHash or QMap) can be streamed without providing
custom \c{operator<<} and \c{operator>>} is deprecated as of Qt 5.7,
because it ignores everything in \c{T} except the base class. There is
no diagnostic. You should always provide these operators for all types
you wish to stream and not rely on Qt-provided stream operators for
base classes.
\sa {qdbustypesystem.html}{Qt D-Bus Type System}, qRegisterMetaType(), QMetaType
*/
/*!
\typedef QDBusMetaType::MarshallFunction
\internal
*/
/*!
\typedef QDBusMetaType::DemarshallFunction
\internal
*/
/*!
\internal
Registers the marshalling and demarshalling functions for meta
type \a metaType.
*/
void QDBusMetaType::registerMarshallOperators(QMetaType metaType, MarshallFunction mf,
DemarshallFunction df)
{
int id = metaType.id();
if (id < 0 || !mf || !df)
return; // error!
auto *ct = customTypes();
if (!ct)
return;
QWriteLocker locker(&ct->lock);
QDBusCustomTypeInfo &info = ct->hash[id];
info.marshall = mf;
info.demarshall = df;
}
/*!
\internal
Executes the marshalling of type \a metaType (whose data is contained in
\a data) to the D-Bus marshalling argument \a arg. Returns \c true if
the marshalling succeeded, or false if an error occurred.
*/
bool QDBusMetaType::marshall(QDBusArgument &arg, QMetaType metaType, const void *data)
{
auto *ct = customTypes();
if (!ct)
return false;
int id = metaType.id();
QDBusMetaTypeId::init();
MarshallFunction mf;
{
QReadLocker locker(&ct->lock);
auto it = ct->hash.constFind(id);
if (it == ct->hash.cend())
return false; // non-existent
const QDBusCustomTypeInfo &info = *it;
if (!info.marshall) {
mf = nullptr; // make gcc happy
return false;
} else
mf = info.marshall;
}
mf(arg, data);
return true;
}
/*!
\internal
Executes the demarshalling of type \a metaType (whose data will be placed in
\a data) from the D-Bus marshalling argument \a arg. Returns \c true if
the demarshalling succeeded, or false if an error occurred.
*/
bool QDBusMetaType::demarshall(const QDBusArgument &arg, QMetaType metaType, void *data)
{
auto *ct = customTypes();
if (!ct)
return false;
int id = metaType.id();
QDBusMetaTypeId::init();
DemarshallFunction df;
{
QReadLocker locker(&ct->lock);
auto it = ct->hash.constFind(id);
if (it == ct->hash.cend())
return false; // non-existent
const QDBusCustomTypeInfo &info = *it;
if (!info.demarshall) {
df = nullptr; // make gcc happy
return false;
} else
df = info.demarshall;
}
#ifndef QT_BOOTSTRAPPED
QDBusArgument copy = arg;
df(copy, data);
#else
Q_UNUSED(arg);
Q_UNUSED(data);
Q_UNUSED(df);
#endif
return true;
}
/*!
\fn QDBusMetaType::signatureToType(const char *signature)
\internal
Returns the Qt meta type id for the given D-Bus signature for exactly one full type, given
by \a signature.
Note: this function only handles the basic D-Bus types.
\sa QDBusUtil::isValidSingleSignature(), typeToSignature(),
QVariant::metaType()
*/
QMetaType QDBusMetaType::signatureToMetaType(const char *signature)
{
if (!signature)
return QMetaType(QMetaType::UnknownType);
QDBusMetaTypeId::init();
switch (signature[0])
{
case DBUS_TYPE_BOOLEAN:
return QMetaType(QMetaType::Bool);
case DBUS_TYPE_BYTE:
return QMetaType(QMetaType::UChar);
case DBUS_TYPE_INT16:
return QMetaType(QMetaType::Short);
case DBUS_TYPE_UINT16:
return QMetaType(QMetaType::UShort);
case DBUS_TYPE_INT32:
return QMetaType(QMetaType::Int);
case DBUS_TYPE_UINT32:
return QMetaType(QMetaType::UInt);
case DBUS_TYPE_INT64:
return QMetaType(QMetaType::LongLong);
case DBUS_TYPE_UINT64:
return QMetaType(QMetaType::ULongLong);
case DBUS_TYPE_DOUBLE:
return QMetaType(QMetaType::Double);
case DBUS_TYPE_STRING:
return QMetaType(QMetaType::QString);
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 QMetaType(QMetaType::QByteArray);
case DBUS_TYPE_STRING:
return QMetaType(QMetaType::QStringList);
case DBUS_TYPE_VARIANT:
return QMetaType(QMetaType::QVariantList);
case DBUS_TYPE_OBJECT_PATH:
return QMetaType::fromType<QList<QDBusObjectPath> >();
case DBUS_TYPE_SIGNATURE:
return QMetaType::fromType<QList<QDBusSignature> >();
}
Q_FALLTHROUGH();
default:
return QMetaType(QMetaType::UnknownType);
}
}
/*!
\fn QDBusMetaType::registerCustomType(QMetaType type, const QByteArray &signature)
\internal
Registers the meta type \a type to be represeneted by the given D-Bus \a signature.
This is used in qdbuscpp2xml for custom types which aren't known to the C++ type system.
*/
void QDBusMetaType::registerCustomType(QMetaType type, const QByteArray &signature)
{
auto *ct = customTypes();
if (!ct)
return;
QWriteLocker locker(&ct->lock);
auto &info = ct->hash[type.id()];
info.signature = signature;
// note how marshall/demarshall are not set, the type is never used at runtime
}
/*!
\fn QDBusMetaType::typeToSignature(int type)
\internal
Returns the D-Bus signature equivalent to the supplied meta type id \a type.
More types can be registered with the qDBusRegisterMetaType() function.
\sa QDBusUtil::isValidSingleSignature(), signatureToType(),
QVariant::metaType()
*/
const char *QDBusMetaType::typeToSignature(QMetaType type)
{
// check if it's a static type
switch (type.id())
{
case QMetaType::UChar:
return DBUS_TYPE_BYTE_AS_STRING;
case QMetaType::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 QMetaType::Int:
return DBUS_TYPE_INT32_AS_STRING;
case QMetaType::UInt:
return DBUS_TYPE_UINT32_AS_STRING;
case QMetaType::LongLong:
return DBUS_TYPE_INT64_AS_STRING;
case QMetaType::ULongLong:
return DBUS_TYPE_UINT64_AS_STRING;
case QMetaType::Double:
return DBUS_TYPE_DOUBLE_AS_STRING;
case QMetaType::QString:
return DBUS_TYPE_STRING_AS_STRING;
case QMetaType::QStringList:
return DBUS_TYPE_ARRAY_AS_STRING
DBUS_TYPE_STRING_AS_STRING; // as
case QMetaType::QByteArray:
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
auto *ct = customTypes();
if (!ct)
return nullptr;
{
QReadLocker locker(&ct->lock);
auto it = ct->hash.constFind(type.id());
if (it == ct->hash.end())
return nullptr;
const QDBusCustomTypeInfo &info = *it;
if (!info.signature.isNull())
return info.signature;
if (!info.marshall)
return nullptr; // 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(&ct->lock);
info = &ct->hash[type.id()];
info->signature = signature;
}
return info->signature;
}
QT_END_NAMESPACE
#endif // QT_NO_DBUS