qdatastream.cpp

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  Reads an unsigned 32-bit integer from the stream and returns a reference to
  the stream.
*/

/*!
  Reads a signed 32-bit integer from the stream 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
	register 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;
}

/*!
  \fn QDataStream &QDataStream::operator>>( Q_UINT64 &i )
  Reads an unsigned 64-bit integer from the stream and returns a reference to
  the stream, or uses the Q_UINT32 operator if 64 bit is not available.
*/

/*!
  Reads a signed 64-bit integer from the stream and returns a reference to
  the stream, or uses the Q_UINT32 operator if 64 bit is not available.
*/

QDataStream &QDataStream::operator>>( Q_INT64 &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_INT64) );
    } else {					// swap bytes
	register uchar *p = (uchar *)(&i);
	char b[sizeof(Q_INT64)];
	dev->readBlock( b, sizeof(Q_INT64) );
	if ( sizeof(Q_INT64) == 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;
}

static double read_double_ascii( QDataStream *s )
{
    register int n = 0;
    char buf[80];
    while ( TRUE ) {
	buf[n] = s->device()->getch();
	if ( buf[n] == '\n' || n > 78 )		// $-terminator
	    break;
	n++;
    }
    buf[n] = '\0';
    return atof( buf );
}


/*!
  Reads a 32-bit floating point number from 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
	f = (float)read_double_ascii( this );
    } else if ( noswap ) {			// no conversion needed
	dev->readBlock( (char *)&f, sizeof(float) );
    } else {					// swap bytes
	register 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;
}


/*!
  Reads a 64-bit floating point number from 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
	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;
}


/*!
  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
  eventually call delete[] on the value.
*/

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 an Q_UINT32 length specifier first, then the
  data (\a l bytes).

  \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
	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.

  \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
 *****************************************************************************/


/*!
  \fn QDataStream &QDataStream::operator<<( Q_UINT8 i )
  Writes an unsigned byte to the stream and returns a reference to
  the stream.
*/

/*!
  Writes a signed byte to the stream.
*/

QDataStream &QDataStream::operator<<( Q_INT8 i )
{
    CHECK_STREAM_PRECOND
    if ( printable && (i == '\\' || !isprint(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;
}


/*!
  \fn QDataStream &QDataStream::operator<<( Q_UINT16 i )
  Writes an unsigned 16-bit integer to the stream and returns a reference
  to the stream.
*/

/*!
  Writes a signed 16-bit integer 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;
}


/*!
  \fn QDataStream &QDataStream::operator<<( Q_UINT32 i )
  Writes an unsigned 32-bit integer to the stream and returns a reference to
  the stream.
*/

/*!
  Writes a signed 32-bit integer 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;
}

/*!
  \fn QDataStream &QDataStream::operator<<( Q_UINT64 i )
  Writes an unsigned 64-bit integer to the stream and returns a reference to
  the stream, or uses the Q_UINT32-operator if 64 bit is not available.
*/

/*!
  Writes a signed 64-bit integer to the stream and returns a reference to
  the stream, or calls the Q_INT32-operator if 64 bit is not available.
*/

QDataStream &QDataStream::operator<<( Q_INT64 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_INT64) );
    } else {					// swap bytes
	register uchar *p = (uchar *)(&i);
	char b[sizeof(Q_INT64)];
	if ( sizeof(Q_INT64) == 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, sizeof(Q_INT64) );
    }
    return *this;
}

/*!
  \fn QDataStream &QDataStream::operator<<( uint i )
  Writes an unsigned integer to the stream as a 32-bit unsigned integer
  (Q_UINT32).
  Returns a reference to the stream.
*/

/*!
  \fn QDataStream &QDataStream::operator<<( int i )
  Writes a signed integer to the stream as a 32-bit signed integer (Q_INT32).
  Returns a reference to the stream.
*/


/*!
  Writes a 32-bit floating point number 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;
}


/*!
  Writes a 64-bit floating point number 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;
}


/*!
  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 an Q_UINT32, followed by \a len bytes from
  \a s.

  \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.

  \sa writeBytes(), QIODevice::writeBlock(), readRawBytes()
*/

QDataStream &QDataStream::writeRawBytes( const char *s, uint len )
{
    CHECK_STREAM_PRECOND
    if ( printable ) {				// write printable
	register char *p = (char *)s;
	while ( len-- )
	    *this << *p++;
    } else {					// write data char array
	dev->writeBlock( s, len );
    }
    return *this;
}

#endif // QT_NO_DATASTREAM