qdbusintrospection.cpp

QT 开发环境里面一个很重要的文件

/****************************************************************************
**
** Copyright (C) 1992-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the tools applications of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file.  Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at [e-mail].
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/

#include "qdbusintrospection_p.h"
#include "qdbusxmlparser_p.h"

/*!
    \class QDBusIntrospection
    \brief Information about introspected objects and interfaces on D-Bus.
    \internal

    This class provides structures and methods for parsing the XML introspection data for D-Bus.
    Normally, you don't have to use the methods provided here: QDBusInterface and QDBusObject will
    do that for you.

    But they may prove useful if the XML data was obtained through other means (like parsing a file).
*/

/*!
    \class QDBusIntrospection::Argument
    \brief One argument to a D-Bus method or signal.

    This struct represents one argument passed to a method or received from a method or signal in
    D-Bus. The struct does not contain information on the direction (input or output).
*/

/*!
    \variable QDBusIntrospection::Argument::type
    The argument type.
*/

/*!
    \variable QDBusIntrospection::Argument::name
    The argument name. The argument name is optional, so this may be a null QString.
*/

/*!
    \fn QDBusIntrospection::Argument::operator==(const Argument &other) const
    Compares this object against \a other and return true if they are the same.
*/

/*!
    \class QDBusIntrospection::Method
    \brief Information about one method.

    This struct represents one method discovered through introspection. A method is composed of
    its \a name, its input arguments, its output arguments, and, optionally, annotations. There are no
    "in-out" arguments.
*/

/*!
    \variable QDBusIntrospection::Method::name
    The method's name.
*/

/*!
    \variable QDBusIntrospection::Method::inputArgs
    A list of the method's input arguments.
*/

/*!
    \variable QDBusIntrospection::Method::outputArgs
    A list of the method's output arguments (i.e., return values).
*/

/*!
    \variable QDBusIntrospection::Method::annotations
    The annotations associated with the method. Each annotation is a pair of strings, where the key
    is of the same format as a D-Bus interface name. The value is arbitrary.
*/

/*!
    \fn QDBusIntrospection::Method::operator==(const Method &other) const
    Compares this object against \a other and return true if they are the same.
*/

/*!
    \class QDBusIntrospection::Signal
    \brief Information about one signal.

    This struct represents one signal discovered through introspection. A signal is composed of
    its \a name, its output arguments, and, optionally, annotations.
*/

/*!
    \variable QDBusIntrospection::Signal::name
    The signal's name.
*/

/*!
    \variable QDBusIntrospection::Signal::outputArgs
    A list of the signal's arguments.
*/

/*!
    \variable QDBusIntrospection::Signal::annotations
    The annotations associated with the signal. Each annotation is a pair of strings, where the key
    is of the same format as a D-Bus interface name. The value is arbitrary.
*/

/*!
    \fn QDBusIntrospection::Signal::operator==(const Signal& other) const
    Compares this object against \a other and return true if they are the same.
*/

/*!
    \class QDBusIntrospection::Property
    \brief Information about one property.

    This struct represents one property discovered through introspection. A property is composed of
    its \a name, its \a type, its \a access rights, and, optionally, annotations.
*/

/*!
    \variable QDBusIntrospection::Property::name
    The property's name.
*/

/*!
    \variable QDBusIntrospection::Property::type
    The property's type.
*/

/*!
    \enum QDBusIntrospection::Property::Access
    The possible access rights for a property:
    \value Read
    \value Write
    \value ReadWrite
*/

/*!
    \variable QDBusIntrospection::Property::access
    The property's access rights.
*/

/*!
    \variable QDBusIntrospection::Property::annotations
    The annotations associated with the property. Each annotation is a pair of strings, where the key
    is of the same format as a D-Bus interface name. The value is arbitrary.
*/

/*!
    \fn QDBusIntrospection::Property::operator==(const Property &other) const
    Compares this object against \a other and return true if they are the same.
*/

/*!
    \class QDBusIntrospection::Interface
    \brief Information about one interface on the bus.

    Each interface on D-Bus has an unique \a name, identifying where that interface was defined.
    Interfaces may have annotations, methods, signals and properties, but none are mandatory.
*/

/*!
    \variable QDBusIntrospection::Interface::name
    The interface's name.
*/

/*!
    \variable QDBusIntrospection::Interface::introspection
    The XML document fragment describing this interface.

    If parsed again through parseInterface, the object returned should have the same contents as
    this object.
*/

/*!
    \variable QDBusIntrospection::Interface::annotations
    The annotations associated with the interface. Each annotation is a pair of strings, where the key
    is of the same format as a D-Bus interface name. The value is arbitrary.
*/

/*!
    \variable QDBusIntrospection::Interface::methods
    The methods available in this interface. Note that method names are not unique (i.e., methods
    can be overloaded with multiple arguments types).
*/

/*!
    \variable QDBusIntrospection::Interface::signals_
    The signals available in this interface. Note that signal names are not unique (i.e., signals
    can be overloaded with multiple argument types).

    This member is called "signals_" because "signals" is a reserved keyword in Qt.
*/

/*!
    \variable QDBusIntrospection::Interface::properties
    The properties available in this interface. Property names are unique.
*/

/*!
    \fn QDBusIntrospection::Interface::operator==(const Interface &other) const
    Compares this object against \a other and return true if they are the same.

    Note that two interfaces are considered to be the same if they have the same name. The internal
    structures in the objects are not compared.
*/

/*!
    \class QDBusIntrospection::Object
    \brief Information about one object on the bus.

    An object on the D-Bus bus is represented by its service and path on the service but, unlike
    interfaces, objects are mutable. That is, their contents can change with time. Therefore,
    while the (service, path) pair uniquely identifies an object, the information contained in
    this struct may no longer represent the object.

    An object can contain interfaces and child (sub) objects.
*/

/*!
    \variable QDBusIntrospection::Object::service
    The object's service name.

    \sa parseObject(), parseObjectTree()
*/

/*!
    \variable QDBusIntrospection::Object::path
    The object's path on the service. This is an absolute path.

    \sa parseObject(), parseObjectTree()
*/

/*!
    \variable QDBusIntrospection::Object::introspection
    The XML document fragment describing this object, its interfaces and sub-objects at the time
    of the parsing.

    The result of parseObject with this XML data should be the same as the Object struct.
*/

/*!
    \variable QDBusIntrospection::Object::interfaces
    The list of interface names in this object.
*/

/*!
    \variable QDBusIntrospection::Object::childObjects
    The list of child object names in this object. Note that this is a relative name, not an
    absolute path. To obtain the absolute path, concatenate with \l
    {QDBusIntrospection::Object::path}{path}.
*/

/*!
    \class QDBusIntrospection::ObjectTree
    \brief Complete information about one object node and its descendency.
    
    This struct contains the same data as QDBusIntrospection::Object, plus the actual data for the
    interfaces and child (sub) objects that was available in the XML document.
*/

/*!
    \variable QDBusIntrospection::ObjectTree::interfaceData
    A map of interfaces and their names.
*/

/*!
    \variable QDBusIntrospection::ObjectTree::childObjectData
    A map of object paths and their data. The map key contains the relative path to the object.

    Note this map contains only the child notes that do have information about the sub-object's
    contents. If the XML data did not contain the information, only the object name will be listed
    in childObjects, but not in childObjectData.
*/

/*!
    \typedef QDBusIntrospection::Annotations
    Contains a QMap of an annotation pair. The annotation's name is stored in the QMap key and
    must be unique. The annotation's value is stored in the QMap's value and is arbitrary.
*/

/*!
    \typedef QDBusIntrospection::Arguments
    Contains a list of arguments to either a Method or a Signal. The arguments' order is important.
*/

/*!
    \typedef QDBusIntrospection::Methods
    Contains a QMap of methods and their names. The method's name is stored in the map's key and
    is not necessarily unique. The order in which multiple methods with the same name are stored
    in this map is undefined.
*/

/*!
    \typedef QDBusIntrospection::Signals
    Contains a QMap of signals and their names. The signal's name is stored in the map's key and
    is not necessarily unique. The order in which multiple signals with the same name are stored
    in this map is undefined.
*/

/*!
    \typedef QDBusIntrospection::Properties
    Contains a QMap of properties and their names. Each property must have a unique name.
*/

/*!
    \typedef QDBusIntrospection::Interfaces
    Contains a QMap of interfaces and their names. Each interface has a unique name.
*/

/*!
    \typedef QDBusIntrospection::Objects
    Contains a QMap of objects and their paths relative to their immediate parent.

    \sa parseObjectTree()
*/

/*!
    Parses the XML document fragment (given by \a xml) containing one interface.

    The first element tag in this XML data must be either \<node\> or \<interface\>. If it is
    \<node\>, then the \<interface\> tag must be a child tag of the \<node\> one.

    If there are multiple interfaces in this XML data, it is undefined which one will be
    returned.
*/
QDBusIntrospection::Interface
QDBusIntrospection::parseInterface(const QString &xml)
{
    // be lazy
    Interfaces ifs = parseInterfaces(xml);
    if (ifs.isEmpty())
        return Interface();

    // return the first in map order (probably alphabetical order)
    return *ifs.constBegin().value();
}

/*!
    Parses the XML document fragment (given by \a xml) containing several interfaces.

    If the first element tag in this document fragment is \<node\>, the interfaces parsed will
    be those found as child elements of the \<node\> tag.
*/
QDBusIntrospection::Interfaces
QDBusIntrospection::parseInterfaces(const QString &xml)
{
    QString null;
    QDBusXmlParser parser(null, null, xml);
    return parser.interfaces();
}

/*!
    Parses the XML document fragment (given by \a xml) containing one object, found at the service
    \a service and path \a path.

    The first element tag in this document must be \<node\>. If that tag does not contain
    a name attribute, the \a path argument will be used to determine the path of this
    object node.

    This function does not parse the interfaces contained in the node, nor sub-object's contents.
    It will only list their names. If you need to know their contents, use parseObjectTree.
*/
QDBusIntrospection::Object
QDBusIntrospection::parseObject(const QString &xml, const QString &service, const QString &path)
{
    QDBusXmlParser parser(service, path, xml);
    QSharedDataPointer<QDBusIntrospection::Object> retval = parser.object();
    if (!retval)
        return QDBusIntrospection::Object();
    return *retval;
}

/*!
    Parses the XML document fragment (given by \a xml) containing one object node and returns all
    the information about the interfaces and sub-objects, found at the service \a service and path
    \a path.

    The Objects map returned will contain the absolute path names in the key.
*/
QDBusIntrospection::ObjectTree
QDBusIntrospection::parseObjectTree(const QString &xml, const QString &service, const QString &path)
{
    QDBusXmlParser parser(service, path, xml);
    QSharedDataPointer<QDBusIntrospection::ObjectTree> retval = parser.objectTree();
    if (!retval)
        return QDBusIntrospection::ObjectTree();
    return *retval;
}