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#include "QtCore/qxmlstream.h"

#if defined(QT_BUILD_XML_LIB) && defined(Q_OS_MAC64)

// No need to define this in the 64-bit Mac libraries.

// Since Qt 4.4 and previous weren't supported in 64-bit, there are

// no QXmlStream* symbols to keep compatibility with

# define QT_NO_XMLSTREAM

#endif

#ifndef QT_NO_XMLSTREAM

#include "qxmlutils_p.h"

#include <qdebug.h>

#include <qfile.h>

#include <stdio.h>

#include <qtextcodec.h>

#include <qstack.h>

#include <qbuffer.h>

#ifndef QT_BOOTSTRAPPED

#include <qcoreapplication.h>

#else

// This specialization of Q_DECLARE_TR_FUNCTIONS is not in qcoreapplication.h,

// because that header depends on QObject being available, which is not the

// case for most bootstrapped applications.

#define Q_DECLARE_TR_FUNCTIONS(context) \

public: \

    static inline QString tr(const char *sourceText, const char *comment = 0) \

        { Q_UNUSED(comment); return QString::fromLatin1(sourceText); } \

    static inline QString trUtf8(const char *sourceText, const char *comment = 0) \

        { Q_UNUSED(comment); return QString::fromLatin1(sourceText); } \

    static inline QString tr(const char *sourceText, const char*, int) \

        { return QString::fromLatin1(sourceText); } \

    static inline QString trUtf8(const char *sourceText, const char*, int) \

        { return QString::fromLatin1(sourceText); } \

private:

#endif

QT_BEGIN_NAMESPACE

#include "qxmlstream_p.h"

/*!

    \enum QXmlStreamReader::TokenType

    This enum specifies the type of token the reader just read.

    \value NoToken The reader has not yet read anything.

    \value Invalid An error has occurred, reported in error() and

    errorString().

    \value StartDocument The reader reports the XML version number in

    documentVersion(), and the encoding as specified in the XML

    document in documentEncoding().  If the document is declared

    standalone, isStandaloneDocument() returns true; otherwise it

    returns false.

    \value EndDocument The reader reports the end of the document.

    \value StartElement The reader reports the start of an element

    with namespaceUri() and name(). Empty elements are also reported

    as StartElement, followed directly by EndElement. The convenience

    function readElementText() can be called to concatenate all

    content until the corresponding EndElement. Attributes are

    reported in attributes(), namespace declarations in

    namespaceDeclarations().

    \value EndElement The reader reports the end of an element with

    namespaceUri() and name().

    \value Characters The reader reports characters in text(). If the

    characters are all white-space, isWhitespace() returns true. If

    the characters stem from a CDATA section, isCDATA() returns true.

    \value Comment The reader reports a comment in text().

    \value DTD The reader reports a DTD in text(), notation

    declarations in notationDeclarations(), and entity declarations in

    entityDeclarations(). Details of the DTD declaration are reported

    in in dtdName(), dtdPublicId(), and dtdSystemId().

    \value EntityReference The reader reports an entity reference that

    could not be resolved.  The name of the reference is reported in

    name(), the replacement text in text().

    \value ProcessingInstruction The reader reports a processing

    instruction in processingInstructionTarget() and

    processingInstructionData().

*/

/*!

    \enum QXmlStreamReader::ReadElementTextBehaviour

    This enum specifies the different behaviours of readElementText().

    \value ErrorOnUnexpectedElement Raise an UnexpectedElementError and return

    what was read so far when a child element is encountered.

    \value IncludeChildElements Recursively include the text from child elements.

    \value SkipChildElements Skip child elements.

    \since 4.6

*/

/*!

    \enum QXmlStreamReader::Error

    This enum specifies different error cases

    \value NoError No error has occurred.

    \value CustomError A custom error has been raised with

    raiseError()

    \value NotWellFormedError The parser internally raised an error

    due to the read XML not being well-formed.

    \value PrematureEndOfDocumentError The input stream ended before a

    well-formed XML document was parsed. Recovery from this error is

    possible if more XML arrives in the stream, either by calling

    addData() or by waiting for it to arrive on the device().

    \value UnexpectedElementError The parser encountered an element

    that was different to those it expected.

*/

/*!

  \class QXmlStreamEntityResolver

  \reentrant

  \since 4.4

  \brief The QXmlStreamEntityResolver class provides an entity

  resolver for a QXmlStreamReader.

  \ingroup xml-tools

 */

/*!

  Destroys the entity resolver.

 */

QXmlStreamEntityResolver::~QXmlStreamEntityResolver()

{

}

/*! \internal

This function is a stub for later functionality.

*/

QString QXmlStreamEntityResolver::resolveEntity(const QString& /*publicId*/, const QString& /*systemId*/)

{

    return QString();

}

/*!

  Resolves the undeclared entity \a name and returns its replacement

  text. If the entity is also unknown to the entity resolver, it

  returns an empty string.

  The default implementation always returns an empty string.

*/

QString QXmlStreamEntityResolver::resolveUndeclaredEntity(const QString &/*name*/)

{

    return QString();

}

#ifndef QT_NO_XMLSTREAMREADER

QString QXmlStreamReaderPrivate::resolveUndeclaredEntity(const QString &name)

{

    if (entityResolver)

        return entityResolver->resolveUndeclaredEntity(name);

    return QString();

}

/*!

   \since 4.4

   Makes \a resolver the new entityResolver().

   The stream reader does \e not take ownership of the resolver. It's

   the callers responsibility to ensure that the resolver is valid

   during the entire life-time of the stream reader object, or until

   another resolver or 0 is set.

   \sa entityResolver()

 */

void QXmlStreamReader::setEntityResolver(QXmlStreamEntityResolver *resolver)

{

    Q_D(QXmlStreamReader);

    d->entityResolver = resolver;

}

/*!

  \since 4.4

  Returns the entity resolver, or 0 if there is no entity resolver.

  \sa setEntityResolver()

 */

QXmlStreamEntityResolver *QXmlStreamReader::entityResolver() const

{

    Q_D(const QXmlStreamReader);

    return d->entityResolver;

}

/*!

  \class QXmlStreamReader

  \reentrant

  \since 4.3

  \brief The QXmlStreamReader class provides a fast parser for reading

  well-formed XML via a simple streaming API.

  \ingroup xml-tools

  QXmlStreamReader is a faster and more convenient replacement for

  Qt's own SAX parser (see QXmlSimpleReader). In some cases it might

  also be a faster and more convenient alternative for use in

  applications that would otherwise use a DOM tree (see QDomDocument).

  QXmlStreamReader reads data either from a QIODevice (see

  setDevice()), or from a raw QByteArray (see addData()).

  Qt provides QXmlStreamWriter for writing XML.

  The basic concept of a stream reader is to report an XML document as

  a stream of tokens, similar to SAX. The main difference between

  QXmlStreamReader and SAX is \e how these XML tokens are reported.

  With SAX, the application must provide handlers (callback functions)

  that receive so-called XML \e events from the parser at the parser's

  convenience.  With QXmlStreamReader, the application code itself

  drives the loop and pulls \e tokens from the reader, one after

  another, as it needs them. This is done by calling readNext(), where

  the reader reads from the input stream until it completes the next

  token, at which point it returns the tokenType(). A set of

  convenient functions including isStartElement() and text() can then

  be used to examine the token to obtain information about what has

  been read. The big advantage of this \e pulling approach is the

  possibility to build recursive descent parsers with it, meaning you

  can split your XML parsing code easily into different methods or

  classes. This makes it easy to keep track of the application's own

  state when parsing XML.

  A typical loop with QXmlStreamReader looks like this:

  \snippet doc/src/snippets/code/src_corelib_xml_qxmlstream.cpp 0

  QXmlStreamReader is a well-formed XML 1.0 parser that does \e not

  include external parsed entities. As long as no error occurs, the

  application code can thus be assured that the data provided by the

  stream reader satisfies the W3C's criteria for well-formed XML. For

  example, you can be certain that all tags are indeed nested and

  closed properly, that references to internal entities have been

  replaced with the correct replacement text, and that attributes have

  been normalized or added according to the internal subset of the

  DTD.

  If an error occurs while parsing, atEnd() and hasError() return

  true, and error() returns the error that occurred. The functions

  errorString(), lineNumber(), columnNumber(), and characterOffset()

  are for constructing an appropriate error or warning message. To

  simplify application code, QXmlStreamReader contains a raiseError()

  mechanism that lets you raise custom errors that trigger the same

  error handling described.

  The \l{QXmlStream Bookmarks Example} illustrates how to use the

  recursive descent technique to read an XML bookmark file (XBEL) with

  a stream reader.

  \section1 Namespaces

  QXmlStream understands and resolves XML namespaces. E.g. in case of

  a StartElement, namespaceUri() returns the namespace the element is

  in, and name() returns the element's \e local name. The combination

  of namespaceUri and name uniquely identifies an element. If a

  namespace prefix was not declared in the XML entities parsed by the

  reader, the namespaceUri is empty.

  If you parse XML data that does not utilize namespaces according to

  the XML specification or doesn't use namespaces at all, you can use

  the element's qualifiedName() instead. A qualified name is the

  element's prefix() followed by colon followed by the element's local

  name() - exactly like the element appears in the raw XML data. Since

  the mapping namespaceUri to prefix is neither unique nor universal,

  qualifiedName() should be avoided for namespace-compliant XML data.

  In order to parse standalone documents that do use undeclared

  namespace prefixes, you can turn off namespace processing completely

  with the \l namespaceProcessing property.

  \section1 Incremental parsing

  QXmlStreamReader is an incremental parser. It can handle the case

  where the document can't be parsed all at once because it arrives in

  chunks (e.g. from multiple files, or over a network connection).

  When the reader runs out of data before the complete document has

  been parsed, it reports a PrematureEndOfDocumentError. When more

  data arrives, either because of a call to addData() or because more

  data is available through the network device(), the reader recovers

  from the PrematureEndOfDocumentError error and continues parsing the

  new data with the next call to readNext().

  For example, if your application reads data from the network using a

  \l{QNetworkAccessManager} {network access manager}, you would issue

  a \l{QNetworkRequest} {network request} to the manager and receive a

  \l{QNetworkReply} {network reply} in return. Since a QNetworkReply

  is a QIODevice, you connect its \l{QNetworkReply::readyRead()}

  {readyRead()} signal to a custom slot, e.g. \c{slotReadyRead()} in

  the code snippet shown in the discussion for QNetworkAccessManager.

  In this slot, you read all available data with

  \l{QNetworkReply::readAll()} {readAll()} and pass it to the XML

  stream reader using addData(). Then you call your custom parsing

  function that reads the XML events from the reader.

  \section1 Performance and memory consumption

  QXmlStreamReader is memory-conservative by design, since it doesn't

  store the entire XML document tree in memory, but only the current

  token at the time it is reported. In addition, QXmlStreamReader

  avoids the many small string allocations that it normally takes to

  map an XML document to a convenient and Qt-ish API. It does this by

  reporting all string data as QStringRef rather than real QString

  objects. QStringRef is a thin wrapper around QString substrings that

  provides a subset of the QString API without the memory allocation

  and reference-counting overhead. Calling

  \l{QStringRef::toString()}{toString()} on any of those objects

  returns an equivalent real QString object.

*/

/*!

  Constructs a stream reader.

  \sa setDevice(), addData()

 */

QXmlStreamReader::QXmlStreamReader()

    : d_ptr(new QXmlStreamReaderPrivate(this))

{

}

/*!  Creates a new stream reader that reads from \a device.

\sa setDevice(), clear()

 */

QXmlStreamReader::QXmlStreamReader(QIODevice *device)

    : d_ptr(new QXmlStreamReaderPrivate(this))

{

    setDevice(device);

}

/*!

  Creates a new stream reader that reads from \a data.

  \sa addData(), clear(), setDevice()

 */

QXmlStreamReader::QXmlStreamReader(const QByteArray &data)

    : d_ptr(new QXmlStreamReaderPrivate(this))

{

    Q_D(QXmlStreamReader);

    d->dataBuffer = data;

}

/*!

  Creates a new stream reader that reads from \a data.

  \sa addData(), clear(), setDevice()

 */

QXmlStreamReader::QXmlStreamReader(const QString &data)

    : d_ptr(new QXmlStreamReaderPrivate(this))

{

    Q_D(QXmlStreamReader);

#ifdef QT_NO_TEXTCODEC

    d->dataBuffer = data.toLatin1();

#else

    d->dataBuffer = d->codec->fromUnicode(data);

    d->decoder = d->codec->makeDecoder();

#endif

    d->lockEncoding = true;

}

/*!

  Creates a new stream reader that reads from \a data.

  \sa addData(), clear(), setDevice()

 */

QXmlStreamReader::QXmlStreamReader(const char *data)

    : d_ptr(new QXmlStreamReaderPrivate(this))

{

    Q_D(QXmlStreamReader);

    d->dataBuffer = QByteArray(data);

}

/*!

  Destructs the reader.

 */

QXmlStreamReader::~QXmlStreamReader()

{

    Q_D(QXmlStreamReader);

    if (d->deleteDevice)

        delete d->device;

}

/*! \fn bool QXmlStreamReader::hasError() const

    Returns \c true if an error has occurred, otherwise \c false.

    \sa errorString(), error()

 */

/*!

    Sets the current device to \a device. Setting the device resets

    the stream to its initial state.

    \sa device(), clear()

*/

void QXmlStreamReader::setDevice(QIODevice *device)

{

    Q_D(QXmlStreamReader);

    if (d->deleteDevice) {

        delete d->device;

        d->deleteDevice = false;

    }

    d->device = device;

    d->init();

}

/*!

    Returns the current device associated with the QXmlStreamReader,

    or 0 if no device has been assigned.

    \sa setDevice()

*/

QIODevice *QXmlStreamReader::device() const

{

    Q_D(const QXmlStreamReader);

    return d->device;

}

/*!

  Adds more \a data for the reader to read. This function does

  nothing if the reader has a device().

  \sa readNext(), clear()

 */

void QXmlStreamReader::addData(const QByteArray &data)

{

    Q_D(QXmlStreamReader);

    if (d->device) {

        qWarning("QXmlStreamReader: addData() with device()");

        return;

    }

    d->dataBuffer += data;

}

/*!

  Adds more \a data for the reader to read. This function does

  nothing if the reader has a device().

  \sa readNext(), clear()

 */

void QXmlStreamReader::addData(const QString &data)

{

    Q_D(QXmlStreamReader);

    d->lockEncoding = true;

#ifdef QT_NO_TEXTCODEC

    addData(data.toLatin1());

#else

    addData(d->codec->fromUnicode(data));

#endif

}

/*!

  Adds more \a data for the reader to read. This function does

  nothing if the reader has a device().

  \sa readNext(), clear()