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diff --git a/qmake/tools/qdatastream.cpp b/qmake/tools/qdatastream.cpp new file mode 100644 index 0000000..9c573c7 --- a/dev/null +++ b/qmake/tools/qdatastream.cpp @@ -0,0 +1,1024 @@ +/**************************************************************************** +** $Id$ +** +** Implementation of QDataStream class +** +** Created : 930831 +** +** Copyright (C) 1992-2000 Trolltech AS. All rights reserved. +** +** This file is part of the tools module of the Qt GUI Toolkit. +** +** This file may be distributed under the terms of the Q Public License +** as defined by Trolltech AS of Norway and appearing in the file +** LICENSE.QPL included in the packaging of this file. +** +** This file may be distributed and/or modified under the terms of the +** GNU General Public License version 2 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. +** +** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition +** 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 +** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. +** +** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for +** information about Qt Commercial License Agreements. +** See http://www.trolltech.com/qpl/ for QPL licensing information. +** See http://www.trolltech.com/gpl/ for GPL licensing information. +** +** Contact info@trolltech.com if any conditions of this licensing are +** not clear to you. +** +**********************************************************************/ + +#include "qdatastream.h" + +#ifndef QT_NO_DATASTREAM +#include "qbuffer.h" +#include <stdio.h> +#include <ctype.h> +#include <stdlib.h> + +/*! + \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 serialization of primitive 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. + + 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 = 5; +// 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 3.1 \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 + *****************************************************************************/ + + +static Q_INT32 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'; + return atol( buf ); +} + + +/*! + \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 = 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_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. +*/ + +/*! + \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 = 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; +} + +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; + 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_ULONG i ) + + Writes an unsigned integer \a i, of the system's word length, to + the stream and returns a reference to the stream. +*/ + +/*! + \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; +} + +/*! + \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 + char buf[32]; + sprintf( buf, "%g\n", (double)f ); + dev->writeBlock( buf, strlen(buf) ); + } 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 + char buf[32]; + sprintf( buf, "%g\n", f ); + dev->writeBlock( buf, strlen(buf) ); + } 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 + 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 |