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qt3/src/tools/qdatastream.cpp

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/****************************************************************************
**
** Implementation of QDataStream class
**
** Created : 930831
**
** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
**
** This file is part of the tools module of the Qt GUI Toolkit.
**
** This file may be used under the terms of the GNU General
** Public License versions 2.0 or 3.0 as published by the Free
** Software Foundation and appearing in the files LICENSE.GPL2
** and LICENSE.GPL3 included in the packaging of this file.
** Alternatively you may (at your option) use any later version
** of the GNU General Public License if such license has been
** publicly approved by Trolltech ASA (or its successors, if any)
** and the KDE Free Qt Foundation.
**
** Please review the following information to ensure GNU General
** Public Licensing requirements will be met:
** http://trolltech.com/products/qt/licenses/licensing/opensource/.
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
** or contact the sales department at sales@trolltech.com.
**
** This file may be used under the terms of the Q Public License as
** defined by Trolltech ASA and appearing in the file LICENSE.QPL
** included in the packaging of this file. Licensees holding valid Qt
** Commercial licenses may use this file in accordance with the Qt
** Commercial License Agreement provided with the Software.
**
** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
** herein.
**
**********************************************************************/
#include "qdatastream.h"
#ifndef QT_NO_DATASTREAM
#include "qbuffer.h"
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#ifndef Q_OS_TEMP
#include <locale.h>
#else
#include "qt_windows.h"
#endif
/*!
\class QDataStream qdatastream.h
\reentrant
\brief The QDataStream class provides serialization of binary data
to a QIODevice.
\ingroup io
A data stream is a binary stream of encoded information which is
100% independent of the host computer's operating system, CPU or
byte order. For example, a data stream that is written by a PC
under Windows can be read by a Sun SPARC running Solaris.
You can also use a data stream to read/write \link #raw raw
unencoded binary data\endlink. If you want a "parsing" input
stream, see QTextStream.
The QDataStream class implements the serialization of C++'s basic
data types, like \c char, \c short, \c int, \c char*, etc.
Serialization of more complex data is accomplished by breaking up
the data into primitive units.
A data stream cooperates closely with a QIODevice. A QIODevice
represents an input/output medium one can read data from and write
data to. The QFile class is an example of an IO device.
Example (write binary data to a stream):
\code
QFile file( "file.dat" );
file.open( IO_WriteOnly );
QDataStream stream( &file ); // we will serialize the data into the file
stream << "the answer is"; // serialize a string
stream << (Q_INT32)42; // serialize an integer
\endcode
Example (read binary data from a stream):
\code
QFile file( "file.dat" );
file.open( IO_ReadOnly );
QDataStream stream( &file ); // read the data serialized from the file
QString str;
Q_INT32 a;
stream >> str >> a; // extract "the answer is" and 42
\endcode
Each item written to the stream is written in a predefined binary
format that varies depending on the item's type. Supported Qt
types include QBrush, QColor, QDateTime, QFont, QPixmap, QString,
QVariant and many others. For the complete list of all Qt types
supporting data streaming see the \link datastreamformat.html
Format of the QDataStream operators \endlink.
For integers it is best to always cast to a Qt integer type for
writing, and to read back into the same Qt integer type. This
ensures that you get integers of the size you want and insulates
you from compiler and platform differences.
To take one example, a \c char* string is written as a 32-bit
integer equal to the length of the string including the NUL byte
('\0'), followed by all the characters of the string including the
NUL byte. When reading a \c char* string, 4 bytes are read to
create the 32-bit length value, then that many characters for the
\c char* string including the NUL are read.
The initial IODevice is usually set in the constructor, but can be
changed with setDevice(). If you've reached the end of the data
(or if there is no IODevice set) atEnd() will return TRUE.
If you want the data to be compatible with an earlier version of
Qt use setVersion().
If you want the data to be human-readable, e.g. for debugging, you
can set the data stream into printable data mode with
setPrintableData(). The data is then written slower, in a bloated
but human readable format.
If you are producing a new binary data format, such as a file
format for documents created by your application, you could use a
QDataStream to write the data in a portable format. Typically, you
would write a brief header containing a magic string and a version
number to give yourself room for future expansion. For example:
\code
QFile file( "file.xxx" );
file.open( IO_WriteOnly );
QDataStream stream( &file );
// Write a header with a "magic number" and a version
stream << (Q_UINT32)0xA0B0C0D0;
stream << (Q_INT32)123;
// Write the data
stream << [lots of interesting data]
\endcode
Then read it in with:
\code
QFile file( "file.xxx" );
file.open( IO_ReadOnly );
QDataStream stream( &file );
// Read and check the header
Q_UINT32 magic;
stream >> magic;
if ( magic != 0xA0B0C0D0 )
return XXX_BAD_FILE_FORMAT;
// Read the version
Q_INT32 version;
stream >> version;
if ( version < 100 )
return XXX_BAD_FILE_TOO_OLD;
if ( version > 123 )
return XXX_BAD_FILE_TOO_NEW;
if ( version <= 110 )
stream.setVersion(1);
// Read the data
stream >> [lots of interesting data];
if ( version > 120 )
stream >> [data new in XXX version 1.2];
stream >> [other interesting data];
\endcode
You can select which byte order to use when serializing data. The
default setting is big endian (MSB first). Changing it to little
endian breaks the portability (unless the reader also changes to
little endian). We recommend keeping this setting unless you have
special requirements.
\target raw
\section1 Reading and writing raw binary data
You may wish to read/write your own raw binary data to/from the
data stream directly. Data may be read from the stream into a
preallocated char* using readRawBytes(). Similarly data can be
written to the stream using writeRawBytes(). Notice that any
encoding/decoding of the data must be done by you.
A similar pair of functions is readBytes() and writeBytes(). These
differ from their \e raw counterparts as follows: readBytes()
reads a Q_UINT32 which is taken to be the length of the data to be
read, then that number of bytes is read into the preallocated
char*; writeBytes() writes a Q_UINT32 containing the length of the
data, followed by the data. Notice that any encoding/decoding of
the data (apart from the length Q_UINT32) must be done by you.
\sa QTextStream QVariant
*/
/*!
\enum QDataStream::ByteOrder
The byte order used for reading/writing the data.
\value BigEndian the default
\value LittleEndian
*/
/*****************************************************************************
QDataStream member functions
*****************************************************************************/
#if defined(QT_CHECK_STATE)
#undef CHECK_STREAM_PRECOND
#define CHECK_STREAM_PRECOND if ( !dev ) { \
qWarning( "QDataStream: No device" ); \
return *this; }
#else
#define CHECK_STREAM_PRECOND
#endif
static int systemWordSize = 0;
static bool systemBigEndian;
static const int DefaultStreamVersion = 6;
// ### On next version bump, QPen::width() should not be restricted to 8-bit values.
// ### On next version bump, when streaming invalid QVariants, just the type should
// be written, no "data" after it
// 6 is default in Qt 3.3
// 5 is default in Qt 3.1
// 4 is default in Qt 3.0
// 3 is default in Qt 2.1
// 2 is the Qt 2.0.x format
// 1 is the Qt 1.x format
/*!
Constructs a data stream that has no IO device.
\sa setDevice()
*/
QDataStream::QDataStream()
{
if ( systemWordSize == 0 ) // get system features
qSysInfo( &systemWordSize, &systemBigEndian );
dev = 0; // no device set
owndev = FALSE;
byteorder = BigEndian; // default byte order
printable = FALSE;
ver = DefaultStreamVersion;
noswap = systemBigEndian;
}
/*!
Constructs a data stream that uses the IO device \a d.
\warning If you use QSocket or QSocketDevice as the IO device \a d
for reading data, you must make sure that enough data is available
on the socket for the operation to successfully proceed;
QDataStream does not have any means to handle or recover from
short-reads.
\sa setDevice(), device()
*/
QDataStream::QDataStream( QIODevice *d )
{
if ( systemWordSize == 0 ) // get system features
qSysInfo( &systemWordSize, &systemBigEndian );
dev = d; // set device
owndev = FALSE;
byteorder = BigEndian; // default byte order
printable = FALSE;
ver = DefaultStreamVersion;
noswap = systemBigEndian;
}
/*!
Constructs a data stream that operates on a byte array, \a a,
through an internal QBuffer device. The \a mode is a
QIODevice::mode(), usually either \c IO_ReadOnly or \c
IO_WriteOnly.
Example:
\code
static char bindata[] = { 231, 1, 44, ... };
QByteArray a;
a.setRawData( bindata, sizeof(bindata) ); // a points to bindata
QDataStream stream( a, IO_ReadOnly ); // open on a's data
stream >> [something]; // read raw bindata
a.resetRawData( bindata, sizeof(bindata) ); // finished
\endcode
The QByteArray::setRawData() function is not for the inexperienced.
*/
QDataStream::QDataStream( QByteArray a, int mode )
{
if ( systemWordSize == 0 ) // get system features
qSysInfo( &systemWordSize, &systemBigEndian );
dev = new QBuffer( a ); // create device
((QBuffer *)dev)->open( mode ); // open device
owndev = TRUE;
byteorder = BigEndian; // default byte order
printable = FALSE;
ver = DefaultStreamVersion;
noswap = systemBigEndian;
}
/*!
Destroys the data stream.
The destructor will not affect the current IO device, unless it is
an internal IO device processing a QByteArray passed in the \e
constructor, in which case the internal IO device is destroyed.
*/
QDataStream::~QDataStream()
{
if ( owndev )
delete dev;
}
/*!
\fn QIODevice *QDataStream::device() const
Returns the IO device currently set.
\sa setDevice(), unsetDevice()
*/
/*!
void QDataStream::setDevice(QIODevice *d )
Sets the IO device to \a d.
\sa device(), unsetDevice()
*/
void QDataStream::setDevice(QIODevice *d )
{
if ( owndev ) {
delete dev;
owndev = FALSE;
}
dev = d;
}
/*!
Unsets the IO device. This is the same as calling setDevice( 0 ).
\sa device(), setDevice()
*/
void QDataStream::unsetDevice()
{
setDevice( 0 );
}
/*!
\fn bool QDataStream::atEnd() const
Returns TRUE if the IO device has reached the end position (end of
the stream or file) or if there is no IO device set; otherwise
returns FALSE, i.e. if the current position of the IO device is
before the end position.
\sa QIODevice::atEnd()
*/
/*!\fn bool QDataStream::eof() const
\obsolete
Returns TRUE if the IO device has reached the end position (end of
stream or file) or if there is no IO device set.
Returns FALSE if the current position of the read/write head of the IO
device is somewhere before the end position.
\sa QIODevice::atEnd()
*/
/*!
\fn int QDataStream::byteOrder() const
Returns the current byte order setting -- either \c BigEndian or
\c LittleEndian.
\sa setByteOrder()
*/
/*!
Sets the serialization byte order to \a bo.
The \a bo parameter can be \c QDataStream::BigEndian or \c
QDataStream::LittleEndian.
The default setting is big endian. We recommend leaving this
setting unless you have special requirements.
\sa byteOrder()
*/
void QDataStream::setByteOrder( int bo )
{
byteorder = bo;
if ( systemBigEndian )
noswap = byteorder == BigEndian;
else
noswap = byteorder == LittleEndian;
}
/*!
\fn bool QDataStream::isPrintableData() const
Returns TRUE if the printable data flag has been set; otherwise
returns FALSE.
\sa setPrintableData()
*/
/*!
\fn void QDataStream::setPrintableData( bool enable )
If \a enable is TRUE, data will be output in a human readable
format. If \a enable is FALSE, data will be output in a binary
format.
If \a enable is TRUE, the write functions will generate output
that consists of printable characters (7 bit ASCII). This output
will typically be a lot larger than the default binary output, and
consequently slower to write.
We recommend only enabling printable data for debugging purposes.
*/
/*!
\fn int QDataStream::version() const
Returns the version number of the data serialization format. In Qt
3.1, this number is 5.
\sa setVersion()
*/
/*!
\fn void QDataStream::setVersion( int v )
Sets the version number of the data serialization format to \a v.
You don't need to set a version if you are using the current
version of Qt.
In order to accommodate new functionality, the datastream
serialization format of some Qt classes has changed in some
versions of Qt. If you want to read data that was created by an
earlier version of Qt, or write data that can be read by a program
that was compiled with an earlier version of Qt, use this function
to modify the serialization format of QDataStream.
\table
\header \i Qt Version \i QDataStream Version
\row \i Qt 3.3 \i11 6
\row \i Qt 3.2 \i11 5
\row \i Qt 3.1 \i11 5
\row \i Qt 3.0 \i11 4
\row \i Qt 2.1.x and Qt 2.2.x \i11 3
\row \i Qt 2.0.x \i11 2
\row \i Qt 1.x \i11 1
\endtable
\sa version()
*/
/*****************************************************************************
QDataStream read functions
*****************************************************************************/
#if defined(Q_OS_HPUX) && !defined(__LP64__)
extern "C" long long __strtoll( const char *, char**, int );
#endif
static Q_INT64 read_int_ascii( QDataStream *s )
{
register int n = 0;
char buf[40];
for ( ;; ) {
buf[n] = s->device()->getch();
if ( buf[n] == '\n' || n > 38 ) // $-terminator
break;
n++;
}
buf[n] = '\0';
#if defined(__LP64__) || defined(Q_OS_OSF)
// sizeof(long) == 8
return strtol(buf, (char **)0, 10);
#else
# if defined(Q_OS_TEMP)
return strtol( buf, (char**)0, 10 );
# elif defined(Q_OS_WIN)
return _atoi64( buf );
# elif defined(Q_OS_HPUX)
return __strtoll( buf, (char**)0, 10 );
# elif defined(Q_OS_MACX) && defined(QT_MACOSX_VERSION) && QT_MACOSX_VERSION < 0x1020
return strtoq( buf, (char**)0, 10 );
# else
return strtoll( buf, (char**)0, 10 ); // C99 function
# endif
#endif
}
/*!
\overload QDataStream &QDataStream::operator>>( Q_UINT8 &i )
Reads an unsigned byte from the stream into \a i, and returns a
reference to the stream.
*/
/*!
Reads a signed byte from the stream into \a i, and returns a
reference to the stream.
*/
QDataStream &QDataStream::operator>>( Q_INT8 &i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
i = (Q_INT8)dev->getch();
if ( i == '\\' ) { // read octal code
char buf[4];
dev->readBlock( buf, 3 );
i = (buf[2] & 0x07)+((buf[1] & 0x07) << 3)+((buf[0] & 0x07) << 6);
}
} else { // data or text
i = (Q_INT8)dev->getch();
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator>>( Q_UINT16 &i )
Reads an unsigned 16-bit integer from the stream into \a i, and
returns a reference to the stream.
*/
/*!
\overload
Reads a signed 16-bit integer from the stream into \a i, and
returns a reference to the stream.
*/
QDataStream &QDataStream::operator>>( Q_INT16 &i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
i = (Q_INT16)read_int_ascii( this );
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&i, sizeof(Q_INT16) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[2];
dev->readBlock( b, 2 );
*p++ = b[1];
*p = b[0];
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator>>( Q_UINT32 &i )
Reads an unsigned 32-bit integer from the stream into \a i, and
returns a reference to the stream.
*/
/*!
\overload
Reads a signed 32-bit integer from the stream into \a i, and
returns a reference to the stream.
*/
QDataStream &QDataStream::operator>>( Q_INT32 &i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
i = (Q_INT32)read_int_ascii( this );
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&i, sizeof(Q_INT32) );
} else { // swap bytes
uchar *p = (uchar *)(&i);
char b[4];
dev->readBlock( b, 4 );
*p++ = b[3];
*p++ = b[2];
*p++ = b[1];
*p = b[0];
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator>>( Q_UINT64 &i )
Reads an unsigned 64-bit integer from the stream, into \a i, and
returns a reference to the stream.
*/
/*!
\overload
Reads a signed 64-bit integer from the stream into \a i, and
returns a reference to the stream.
*/
QDataStream &QDataStream::operator>>( Q_INT64 &i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
i = read_int_ascii( this );
} else if ( version() < 6 ) {
Q_UINT32 i1, i2;
*this >> i2 >> i1;
i = ((Q_UINT64)i1 << 32) + i2;
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&i, sizeof(Q_INT64) );
} else { // swap bytes
uchar *p = (uchar *)(&i);
char b[8];
dev->readBlock( b, 8 );
*p++ = b[7];
*p++ = b[6];
*p++ = b[5];
*p++ = b[4];
*p++ = b[3];
*p++ = b[2];
*p++ = b[1];
*p = b[0];
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator>>( Q_ULONG &i )
Reads an unsigned integer of the system's word length from the
stream, into \a i, and returns a reference to the stream.
*/
#if !defined(Q_OS_WIN64)
/*!
\overload
Reads a signed integer of the system's word length from the stream
into \a i, and returns a reference to the stream.
*/
QDataStream &QDataStream::operator>>( Q_LONG &i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
i = (Q_LONG)read_int_ascii( this );
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&i, sizeof(Q_LONG) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[sizeof(Q_LONG)];
dev->readBlock( b, sizeof(Q_LONG) );
for ( int j = sizeof(Q_LONG); j; )
*p++ = b[--j];
}
return *this;
}
#endif
static double read_double_ascii( QDataStream *s )
{
register int n = 0;
char buf[80];
for ( ;; ) {
buf[n] = s->device()->getch();
if ( buf[n] == '\n' || n > 78 ) // $-terminator
break;
n++;
}
buf[n] = '\0';
return atof( buf );
}
/*!
\overload
Reads a 32-bit floating point number from the stream into \a f,
using the standard IEEE754 format. Returns a reference to the
stream.
*/
QDataStream &QDataStream::operator>>( float &f )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
f = (float)read_double_ascii( this );
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&f, sizeof(float) );
} else { // swap bytes
uchar *p = (uchar *)(&f);
char b[4];
dev->readBlock( b, 4 );
*p++ = b[3];
*p++ = b[2];
*p++ = b[1];
*p = b[0];
}
return *this;
}
/*!
\overload
Reads a 64-bit floating point number from the stream into \a f,
using the standard IEEE754 format. Returns a reference to the
stream.
*/
QDataStream &QDataStream::operator>>( double &f )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
f = read_double_ascii( this );
} else if ( noswap ) { // no conversion needed
dev->readBlock( (char *)&f, sizeof(double) );
} else { // swap bytes
register uchar *p = (uchar *)(&f);
char b[8];
dev->readBlock( b, 8 );
*p++ = b[7];
*p++ = b[6];
*p++ = b[5];
*p++ = b[4];
*p++ = b[3];
*p++ = b[2];
*p++ = b[1];
*p = b[0];
}
return *this;
}
/*!
\overload
Reads the '\0'-terminated string \a s from the stream and returns
a reference to the stream.
Space for the string is allocated using \c new -- the caller must
destroy it with delete[].
*/
QDataStream &QDataStream::operator>>( char *&s )
{
uint len = 0;
return readBytes( s, len );
}
/*!
Reads the buffer \a s from the stream and returns a reference to
the stream.
The buffer \a s is allocated using \c new. Destroy it with the \c
delete[] operator. If the length is zero or \a s cannot be
allocated, \a s is set to 0.
The \a l parameter will be set to the length of the buffer.
The serialization format is a Q_UINT32 length specifier first,
then \a l bytes of data. Note that the data is \e not encoded.
\sa readRawBytes(), writeBytes()
*/
QDataStream &QDataStream::readBytes( char *&s, uint &l )
{
CHECK_STREAM_PRECOND
Q_UINT32 len;
*this >> len; // first read length spec
l = (uint)len;
if ( len == 0 || eof() ) {
s = 0;
return *this;
} else {
s = new char[len]; // create char array
Q_CHECK_PTR( s );
if ( !s ) // no memory
return *this;
return readRawBytes( s, (uint)len );
}
}
/*!
Reads \a len bytes from the stream into \a s and returns a
reference to the stream.
The buffer \a s must be preallocated. The data is \e not encoded.
\sa readBytes(), QIODevice::readBlock(), writeRawBytes()
*/
QDataStream &QDataStream::readRawBytes( char *s, uint len )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
register Q_INT8 *p = (Q_INT8*)s;
if ( version() < 4 ) {
while ( len-- ) {
Q_INT32 tmp;
*this >> tmp;
*p++ = tmp;
}
} else {
while ( len-- )
*this >> *p++;
}
} else { // read data char array
dev->readBlock( s, len );
}
return *this;
}
/*****************************************************************************
QDataStream write functions
*****************************************************************************/
/*!
\overload QDataStream &QDataStream::operator<<( Q_UINT8 i )
Writes an unsigned byte, \a i, to the stream and returns a
reference to the stream.
*/
/*!
Writes a signed byte, \a i, to the stream and returns a reference
to the stream.
*/
QDataStream &QDataStream::operator<<( Q_INT8 i )
{
CHECK_STREAM_PRECOND
if ( printable && (i == '\\' || !isprint((uchar) i)) ) {
char buf[6]; // write octal code
buf[0] = '\\';
buf[1] = '0' + ((i >> 6) & 0x07);
buf[2] = '0' + ((i >> 3) & 0x07);
buf[3] = '0' + (i & 0x07);
buf[4] = '\0';
dev->writeBlock( buf, 4 );
} else {
dev->putch( i );
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator<<( Q_UINT16 i )
Writes an unsigned 16-bit integer, \a i, to the stream and returns
a reference to the stream.
*/
/*!
\overload
Writes a signed 16-bit integer, \a i, to the stream and returns a
reference to the stream.
*/
QDataStream &QDataStream::operator<<( Q_INT16 i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
char buf[16];
sprintf( buf, "%d\n", i );
dev->writeBlock( buf, strlen(buf) );
} else if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&i, sizeof(Q_INT16) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[2];
b[1] = *p++;
b[0] = *p;
dev->writeBlock( b, 2 );
}
return *this;
}
/*!
\overload
Writes a signed 32-bit integer, \a i, to the stream and returns a
reference to the stream.
*/
QDataStream &QDataStream::operator<<( Q_INT32 i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
char buf[16];
sprintf( buf, "%d\n", i );
dev->writeBlock( buf, strlen(buf) );
} else if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&i, sizeof(Q_INT32) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[4];
b[3] = *p++;
b[2] = *p++;
b[1] = *p++;
b[0] = *p;
dev->writeBlock( b, 4 );
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator<<( Q_UINT64 i )
Writes an unsigned 64-bit integer, \a i, to the stream and returns a
reference to the stream.
*/
/*!
\overload
Writes a signed 64-bit integer, \a i, to the stream and returns a
reference to the stream.
*/
QDataStream &QDataStream::operator<<( Q_INT64 i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
char buf[16];
#ifdef Q_OS_WIN
sprintf( buf, "%I64d\n", i );
#else
sprintf( buf, "%lld\n", i );
#endif
dev->writeBlock( buf, strlen(buf) );
} else if ( version() < 6 ) {
Q_UINT32 i1 = i & 0xffffffff;
Q_UINT32 i2 = i >> 32;
*this << i2 << i1;
} else if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&i, sizeof(Q_INT64) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[8];
b[7] = *p++;
b[6] = *p++;
b[5] = *p++;
b[4] = *p++;
b[3] = *p++;
b[2] = *p++;
b[1] = *p++;
b[0] = *p;
dev->writeBlock( b, 8 );
}
return *this;
}
/*!
\overload QDataStream &QDataStream::operator<<( Q_ULONG i )
Writes an unsigned integer \a i, of the system's word length, to
the stream and returns a reference to the stream.
*/
#if !defined(Q_OS_WIN64)
/*!
\overload
Writes a signed integer \a i, of the system's word length, to the
stream and returns a reference to the stream.
*/
QDataStream &QDataStream::operator<<( Q_LONG i )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
char buf[20];
sprintf( buf, "%ld\n", i );
dev->writeBlock( buf, strlen(buf) );
} else if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&i, sizeof(Q_LONG) );
} else { // swap bytes
register uchar *p = (uchar *)(&i);
char b[sizeof(Q_LONG)];
for ( int j = sizeof(Q_LONG); j; )
b[--j] = *p++;
dev->writeBlock( b, sizeof(Q_LONG) );
}
return *this;
}
#endif
/*!
\overload QDataStream &QDataStream::operator<<( Q_UINT32 i )
Writes an unsigned integer, \a i, to the stream as a 32-bit
unsigned integer (Q_UINT32). Returns a reference to the stream.
*/
/*!
\overload
Writes a 32-bit floating point number, \a f, to the stream using
the standard IEEE754 format. Returns a reference to the stream.
*/
QDataStream &QDataStream::operator<<( float f )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
QString num = QString::number((double)f);
dev->writeBlock(num.latin1(), num.length());
dev->putch('\n');
} else {
float g = f; // fixes float-on-stack problem
if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&g, sizeof(float) );
} else { // swap bytes
register uchar *p = (uchar *)(&g);
char b[4];
b[3] = *p++;
b[2] = *p++;
b[1] = *p++;
b[0] = *p;
dev->writeBlock( b, 4 );
}
}
return *this;
}
/*!
\overload
Writes a 64-bit floating point number, \a f, to the stream using
the standard IEEE754 format. Returns a reference to the stream.
*/
QDataStream &QDataStream::operator<<( double f )
{
CHECK_STREAM_PRECOND
if ( printable ) { // printable data
QString num = QString::number((double)f);
dev->writeBlock(num.latin1(), num.length());
dev->putch('\n');
} else if ( noswap ) { // no conversion needed
dev->writeBlock( (char *)&f, sizeof(double) );
} else { // swap bytes
register uchar *p = (uchar *)(&f);
char b[8];
b[7] = *p++;
b[6] = *p++;
b[5] = *p++;
b[4] = *p++;
b[3] = *p++;
b[2] = *p++;
b[1] = *p++;
b[0] = *p;
dev->writeBlock( b, 8 );
}
return *this;
}
/*!
\overload
Writes the '\0'-terminated string \a s to the stream and returns a
reference to the stream.
The string is serialized using writeBytes().
*/
QDataStream &QDataStream::operator<<( const char *s )
{
if ( !s ) {
*this << (Q_UINT32)0;
return *this;
}
uint len = qstrlen( s ) + 1; // also write null terminator
*this << (Q_UINT32)len; // write length specifier
return writeRawBytes( s, len );
}
/*!
Writes the length specifier \a len and the buffer \a s to the
stream and returns a reference to the stream.
The \a len is serialized as a Q_UINT32, followed by \a len bytes
from \a s. Note that the data is \e not encoded.
\sa writeRawBytes(), readBytes()
*/
QDataStream &QDataStream::writeBytes(const char *s, uint len)
{
CHECK_STREAM_PRECOND
*this << (Q_UINT32)len; // write length specifier
if ( len )
writeRawBytes( s, len );
return *this;
}
/*!
Writes \a len bytes from \a s to the stream and returns a
reference to the stream. The data is \e not encoded.
\sa writeBytes(), QIODevice::writeBlock(), readRawBytes()
*/
QDataStream &QDataStream::writeRawBytes( const char *s, uint len )
{
CHECK_STREAM_PRECOND
if ( printable ) { // write printable
if ( version() < 4 ) {
register char *p = (char *)s;
while ( len-- )
*this << *p++;
} else {
register Q_INT8 *p = (Q_INT8*)s;
while ( len-- )
*this << *p++;
}
} else { // write data char array
dev->writeBlock( s, len );
}
return *this;
}
#endif // QT_NO_DATASTREAM